Systems and methods for endoluminal valve creation

ABSTRACT

A device for manipulating tissue at a vessel includes an elongated member having a proximal end and a distal end, a guide member at the distal end of the elongated member, the guide member having a blunt distal tip for engagement against an interior wall of the vessel, and a tissue cutting device at the distal end of the elongated member, wherein the tissue cutting device has a sharp tip that is proximal to the blunt distal tip of the guide member.

RELATED APPLICATION DATA

This application claims priority to and the benefit of U.S. ProvisionalPatent Application Nos. 61/308,503, filed on Feb. 26, 2010, pending,61/349,349, filed on May 28, 2010, pending, 61/393,996, filed on Oct.18, 2010, pending, and 61/420,307, filed on Dec. 6, 2010, pending, theentire disclosure of all of which is expressly incorporated by referenceherein.

GOVERNMENT RIGHTS

This invention was made with Government support under contract RR025742awarded by the National Institutes of Health. The Government has certainrights in this invention.

FIELD

The present application pertains generally to medical systems andmethods for creation of an autologous tissue valves within a mammalianbody.

BACKGROUND

Venous reflux is a medical condition affecting the circulation of blood,such as in the lower extremities. The valves in the vessel that normallyforce blood back towards the heart cannot function properly. As aresult, blood pools up in the legs, and the veins of the legs becomedistended. Applicant of the subject application determines that newsystems and methods for treating venous reflux would be desirable.

SUMMARY

In accordance with some embodiments, a device for manipulating tissue ata vessel includes an elongated member having a proximal end and a distalend, a guide member at the distal end of the elongated member, the guidemember having a blunt distal tip for engagement against an interior wallof the vessel, and a tissue cutting device at the distal end of theelongated member, wherein the tissue cutting device has a sharp tip thatis proximal to the blunt distal tip of the guide member.

In accordance with any of the embodiments described herein, the tissuecutting device is configured to cut tissue at the interior wall of thevessel while the guide member engages against the interior wall of thevessel.

In accordance with any of the embodiments described herein, the guidemember is configured to orient the tissue cutting device at a desiredangle relative to the interior wall of the vessel.

In accordance with any of the embodiments described herein, the guidemember is configured to apply pressure at a surface of the interior wallof the vessel to thereby provide tension at the surface.

In accordance with any of the embodiments described herein, the tissuecutting device comprises a tube having a lumen for delivering fluid.

In accordance with any of the embodiments described herein, the devicefurther includes a source of agent for delivering the agent to thetissue cutting device.

In accordance with any of the embodiments described herein, the agentcomprises a contrast agent.

In accordance with any of the embodiments described herein, the tissuecutting device has a tapered configuration.

In accordance with any of the embodiments described herein, the tissuecutting device is tapered proximally from a first longitudinal side ofthe cutting device to a second longitudinal side of the cutting devicethat is opposite from the first longitudinal side, the firstlongitudinal side of the cutting device being further from alongitudinal axis of the elongated member than the second longitudinalside.

In accordance with any of the embodiments described herein, a proximalend of the guide member and a proximal end of the tissue cutting devicecollectively form a stopper for preventing tissue located between theguide member and the tissue cutting device from moving proximally pastthe stopper.

In accordance with any of the embodiments described herein, the guidemember and the elongated member have a unity configuration.

In accordance with any of the embodiments described herein, the tissuecutting device and the elongated member have a unity configuration.

In accordance with any of the embodiments described herein, a length ofthe tissue cutting device dictates how far the tissue cutting device isto penetrate into the interior wall of the vessel.

In accordance with other embodiments, a device for manipulating tissueat a vessel includes an elongated member having a proximal end and adistal end, a guide member extending distally from the distal end of theelongated member, the guide member configured for engagement against aninterior wall of the vessel, a tissue cutting device extending distallyfrom the distal end of the elongated member, wherein a proximal end ofthe guide member and a proximal end of the tissue cutting devicecollectively form a stopper for preventing tissue located between theguide member and the tissue cutting device from moving proximally pastthe stopper.

In accordance with any of the embodiments described herein, the guidemember has a blunt distal tip, and the tissue cutting device has a sharptip that is proximal to the blunt distal tip of the guide member, andthe stopper is configured for preventing the cut tissue from movingproximally past the stopper.

In accordance with any of the embodiments described herein, the tissuecutting device is configured to cut tissue at the interior wall of thevessel while the guide member engages against the interior wall of thevessel.

In accordance with any of the embodiments described herein, the guidemember is configured to orient the tissue cutting device at a desiredangle relative to the interior wall of the vessel.

In accordance with any of the embodiments described herein, the guidemember is configured to apply pressure at a surface of the interior wallof the vessel to thereby provide tension at the surface.

In accordance with any of the embodiments described herein, the tissuecutting device comprises a tube having a lumen for delivering fluid.

In accordance with any of the embodiments described herein, the devicefurther includes a source of agent for delivering the agent to thetissue cutting device.

In accordance with any of the embodiments described herein, the agentcomprises a contrast agent.

In accordance with any of the embodiments described herein, the tissuecutting device has a tapered configuration.

In accordance with any of the embodiments described herein, the tissuecutting device is tapered from a first longitudinal side of the cuttingdevice to a second longitudinal side of the cutting device that isopposite from the first longitudinal side, the first longitudinal sideof the cutting device being further from a longitudinal axis of theelongated member than the second longitudinal side.

In accordance with any of the embodiments described herein, the guidemember and the elongated member have a unity configuration.

In accordance with any of the embodiments described herein, the tissuecutting device and the elongated member have a unity configuration.

In accordance with any of the embodiments described herein, a length ofthe tissue cutting device dictates how far the tissue cutting device isto penetrate into the interior wall of the vessel.

In accordance with other embodiments, a method of manipulating tissue ata vessel includes applying tension by a first device to a surface of aninterior wall of the vessel, and using a second device to penetratetissue at the interior wall of the vessel while the tension is appliedby the first device to the surface of the interior wall of the vessel.

In accordance with any of the embodiments described herein, the methodfurther includes advancing the second device distally inside theinterior wall of the vessel until a stopper at a proximal end of thesecond device engages with vessel tissue.

In accordance with any of the embodiments described herein, the seconddevice has a lumen, and the method further comprises delivering fluidthrough the lumen of the second device into a space that is inside theinterior wall of the vessel.

In accordance with any of the embodiments described herein, the fluid isdelivered to enlarge the space inside the interior wall of the vessel.

In accordance with any of the embodiments described herein, the seconddevice penetrates the tissue to create an opening at the tissue, andwherein the method further comprises increasing a size of the opening.

In accordance with any of the embodiments described herein, the space isenlarged to create a flap inside the vessel.

In accordance with any of the embodiments described herein, the methodfurther includes securing the flap relative to the vessel.

In accordance with any of the embodiments described herein, the seconddevice penetrates the tissue to create an opening at the tissue, andwherein the method further comprises increasing a size of the opening.

In accordance with any of the embodiments described herein, the firstdevice is also used to orient the second device so that the seconddevice is at a desired angle relative to the surface of the interiorwall of the vessel.

In accordance with any of the embodiments described herein, the desiredangle comprises an acute angle that is less than 45°.

In accordance with any of the embodiments described herein, the firstdevice comprises an expandable member.

In accordance with other embodiments, a method of manipulating tissue ata vessel includes delivering a first device and a second devicepercutaneously into a lumen of a vessel, using the first device toorient the second device at an angle relative to an interior wall of thevessel, and penetrate through a surface at the interior wall of thevessel at the angle using the second device.

In accordance with any of the embodiments described herein, the methodfurther includes applying tension by a third device to the surface ofthe interior wall of the vessel.

In accordance with any of the embodiments described herein, the methodfurther includes advancing the second device distally inside theinterior wall of the vessel until a stopper at a proximal end of thesecond device engages with the vessel tissue.

In accordance with any of the embodiments described herein, the seconddevice has a lumen, and the method further comprises delivering fluidthrough the lumen of the second device into a space that is inside theinterior wall of the vessel.

In accordance with any of the embodiments described herein, the fluid isdelivered to enlarge the space inside the interior wall of the vessel.

In accordance with any of the embodiments described herein, the seconddevice penetrates the surface to create an opening at the interior wallof the vessel, and wherein the method further comprises increasing asize of the opening after the space inside the interior wall isenlarged.

In accordance with any of the embodiments described herein, the space isenlarged to create a flap inside the vessel.

In accordance with any of the embodiments described herein, the methodfurther includes securing the flap relative to the vessel.

In accordance with any of the embodiments described herein, the seconddevice penetrates the surface to create an opening at the interior wallof the vessel, and wherein the method further comprises increasing asize of the opening.

In accordance with other embodiments, a method of manipulating tissue ata vessel includes inserting a tubular structure into a first wallportion of the vessel, and using the tubular structure to deliver fluidinto the first wall portion of the vessel to create a pocket inside thefirst wall portion of the vessel.

In accordance with any of the embodiments described herein, the fluid isdelivered in pulses.

In accordance with any of the embodiments described herein, the methodfurther includes advancing a distal end of the tubular structuredistally while the distal end is inside the first wall portion of thevessel.

In accordance with any of the embodiments described herein, the methodfurther includes delivering additional fluid into the first wall portionof the vessel after the distal end of the tubular structure has beenadvanced distally.

In accordance with any of the embodiments described herein, the createdpocket has a length measured along a longitudinal axis of the vesselthat is sufficient to form a flap from the first wall portion of thevessel.

In accordance with any of the embodiments described herein, the tubularstructure comprises a distal tip and a port at the distal tip, and thefluid is delivered through the port.

In accordance with any of the embodiments described herein, the tubularstructure comprises a side port, and the fluid is delivered through theside port.

In accordance with any of the embodiments described herein, the pocketis created by using the fluid to dissect a layer of tissue from thevessel.

In accordance with any of the embodiments described herein, the layer oftissue forms a flap.

In accordance with any of the embodiments described herein, the methodfurther includes securing the flap to a second wall portion of thevessel.

In accordance with any of the embodiments described herein, the secondwall portion is opposite from the first wall portion.

In accordance with any of the embodiments described herein, the tubularstructure is inserted through an opening at an interior surface of thevessel, and the method comprises increasing the size of the opening.

In accordance with other embodiments, a system for manipulating tissueat a vessel includes a tubular structure sized for insertion into afirst wall portion of the vessel, and a fluid source coupled to aproximal end of the tubular structure, wherein the fluid source isconfigured to deliver fluid into the first wall portion of the vessel tocreate a pocket inside the first wall portion of the vessel, and whereinthe fluid source is configured to deliver the fluid with a fluidpressure that is strong enough to dissect tissue in the first wallportion of the vessel, but insufficient to puncture through the firstwall portion.

In accordance with any of the embodiments described herein, the fluiddelivery device is configured to deliver the fluid in pulses.

In accordance with any of the embodiments described herein, the tubularstructure comprises a distal tip and a port at the distal tip.

In accordance with any of the embodiments described herein, the tubularstructure comprises a side port.

In accordance with any of the embodiments described herein, the systemfurther includes a guide member coupled to the tubular structure.

In accordance with any of the embodiments described herein, the guidedevice comprises an elongated structure having a blunt distal tip.

In accordance with any of the embodiments described herein, theelongated structure and the tubular structure are coupled together toform a stopper.

In accordance with any of the embodiments described herein, the bluntdistal tip of the elongated structure is distal to a distal tip of thetubular structure.

In accordance with any of the embodiments described herein, the systemfurther includes securing mechanism for securing a part of the firstwall portion to a second wall portion of the vessel.

In accordance with any of the embodiments described herein, the secondwall portion is opposite from the first wall portion.

In accordance with some embodiments, a method of manipulating tissue ata vessel includes advancing a device distally relative to an opening atan interior surface of the vessel, and into a first wall portion of avessel until an entirety of the device is within the wall of the vessel,the device having a distal end, a proximal end, and a cutting elementcoupled to the proximal end, and using the cutting element to increase asize of the opening by retracting the device proximally.

In accordance with any of the embodiments described herein, the devicecomprises an expandable member.

In accordance with any of the embodiments described herein, theexpandable member comprises an inflatable member.

In accordance with any of the embodiments described herein, theexpandable member comprises a cage.

In accordance with any of the embodiments described herein, the cuttingelement comprises a blade.

In accordance with any of the embodiments described herein, the methodfurther includes creating the opening before the entirety of the deviceis inserted into the first wall portion of the vessel.

In accordance with any of the embodiments described herein, the methodfurther includes creating the opening using the device.

In accordance with any of the embodiments described herein, the methodfurther includes using the device to create a flap from a portion of thevessel, wherein the increased size of the opening results in the flaphaving a desired width.

In accordance with any of the embodiments described herein, the methodfurther includes securing one end of the flap relative to a second wallportion of the vessel.

In accordance with any of the embodiments described herein, the secondwall portion is opposite from the first wall portion.

In accordance with other embodiments, a system for manipulating tissueat a vessel includes a tissue separator sized for insertion into a firstwall portion of a vessel through an opening at an interior surface ofthe vessel, the tissue separator having a distal end, a proximal end,and a cutting element coupled to the proximal end, wherein the cuttingelement is configured to increase a size of the opening.

In accordance with any of the embodiments described herein, the tissueseparator comprises an expandable member.

In accordance with any of the embodiments described herein, theexpandable member comprises an inflatable member.

In accordance with any of the embodiments described herein, theexpandable member comprises a cage.

In accordance with any of the embodiments described herein, theexpandable member, when expanded, has a shape and size configured tocreate a flap from the first wall portion of the vessel.

In accordance with any of the embodiments described herein, theexpandable member has an asymmetric configuration.

In accordance with any of the embodiments described herein, the systemfurther includes securing device for securing one end of the flaprelative to a second wall portion of the vessel.

In accordance with any of the embodiments described herein, the secondwall portion is opposite from the first wall portion.

In accordance with any of the embodiments described herein, the cuttingelement comprises a blade.

In accordance with any of the embodiments described herein, the systemfurther includes a device for creating the opening before the tissueseparator is inserted into the first wall portion of the vessel.

In accordance with any of the embodiments described herein, the deviceis coupled to the tissue separator.

In accordance with any of the embodiments described herein, the deviceis separate from the tissue separator.

In accordance with other embodiments, a method of manipulating tissue ata vessel includes inserting a device percutaneously into a lumen of avessel, advancing the device inside the lumen of the vessel until thedevice reaches a location in the vessel that has a flap, and using thedevice to secure the flap relative to an interior surface of the vessel.

In accordance with any of the embodiments described herein, the devicecomprises a stitching material, and the act of using the device tosecure the flap comprises using the stitching material to secure theflap relative to the interior surface of the vessel.

In accordance with any of the embodiments described herein, the devicecomprises a pin, and the act of using the device to secure the flapcomprises using the pin to secure the flap relative to the interiorsurface of the vessel.

In accordance with any of the embodiments described herein, the devicecomprises tissue glue.

In accordance with any of the embodiments described herein, the flap islocated on a first side of the vessel, and the interior surface islocated on a second side of the vessel that is opposite from the firstside.

In accordance with any of the embodiments described herein, the methodfurther includes moving the flap from the first side of the vesseltowards the second side of the vessel.

In accordance with any of the embodiments described herein, the flap hasan end that is separated from the vessel, the end of the flap located ata first position along the vessel, and wherein the flap is moved toreach the second side of the vessel, the end of the flap is located at asecond position along the vessel that is offset from the first position.

In accordance with any of the embodiments described herein, the flap iscreated from a portion of the vessel, and has a first end that isseparated from the vessel, and a second end that extends from thevessel.

In accordance with any of the embodiments described herein, the methodfurther includes inserting a cutting device percutaneously into thelumen of the vessel, and using the cutting device in a process to createthe flap from a portion of the vessel.

In accordance with any of the embodiments described herein, the act ofusing the cutting device comprises placing the cutting device inside awall of the vessel.

In accordance with any of the embodiments described herein, the cuttingdevice comprises a blade.

In accordance with any of the embodiments described herein, the cuttingdevice comprises a tube for delivering fluid.

In accordance with any of the embodiments described herein, the interiorsurface comprises another flap.

In accordance with other embodiments, a system for manipulating tissueat a vessel includes a first device having an elongated configuration,and carrying a securing mechanism, wherein the first device is sized forinsertion into a lumen of a vessel, and wherein the securing mechanismis configured to secure a flap in the vessel relative to an interiorsurface of the vessel.

In accordance with any of the embodiments described herein, the securingmechanism comprises a stitching material.

In accordance with any of the embodiments described herein, the securingmechanism comprises a pin.

In accordance with any of the embodiments described herein, the securingmechanism comprises tissue glue.

In accordance with any of the embodiments described herein, the flap islocated on a first side of the vessel, and the interior surface islocated on a second side of the vessel that is opposite from the firstside, and wherein the system further comprising a positioning mechanismfor moving the flap from the first side of the vessel towards the secondside of the vessel.

In accordance with any of the embodiments described herein, the flap hasan end that is separated from the vessel, the end of the flap located ata first position along the vessel, and wherein the positioning mechanismis configured to move the flap so that when the flap reaches the secondside of the vessel, the end of the flap is located at a second positionalong the vessel that is offset from the first position.

In accordance with any of the embodiments described herein, the systemfurther includes a cutting device sized for insertion into the lumen ofthe vessel, wherein the cutting device is configured to penetrate into awall of the vessel.

In accordance with any of the embodiments described herein, the cuttingdevice comprises a blade.

In accordance with any of the embodiments described herein, the cuttingdevice comprises a tube for delivering fluid.

In accordance with any of the embodiments described herein, the cuttingdevice is configured to create the flap from a portion of the vessel.

Other and further aspects and features will be evident from reading thefollowing detailed description of the embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate the design and utility of embodiments, in whichsimilar elements are referred to by common reference numerals. Thesedrawings are not necessarily drawn to scale. In order to betterappreciate how the above-recited and other advantages and objects areobtained, a more particular description of the embodiments will berendered, which are illustrated in the accompanying drawings. Thesedrawings depict only typical embodiments and are not therefore to beconsidered limiting of its scope.

FIGS. 1-6 illustrate components of a valve creation system in accordancewith some embodiments.

FIGS. 7-12 illustrate a method of creating a valve in accordance withsome embodiments.

FIGS. 13a-13e depict different aspects of a valve geometry in accordancewith some embodiments.

FIG. 14 illustrates an ultrasound device in accordance with someembodiments.

FIG. 15 illustrates a conduit mechanism with a pre-formed curvilinearconfiguration in accordance with some embodiments.

FIG. 16 illustrates a conduit mechanism having an angling mechanism inaccordance with some embodiments.

FIG. 17 illustrates an angling mechanism being embodied as thesub-intimal access mechanism in accordance with some embodiments.

FIG. 18 illustrates an angling mechanism embodied as a curved stylet inaccordance with some embodiments.

FIG. 19 illustrates a cage as a wall-tensioning mechanism in accordancewith some embodiments.

FIG. 20 illustrates another conduit mechanism in accordance with someembodiments.

FIG. 21 illustrates a conduit mechanism being used with an expandablemember in accordance with some embodiments.

FIGS. 22-26 illustrate different sub-intimal access mechanisms inaccordance with different embodiments.

FIGS. 27-29 illustrate different hydrodissectors in accordance withdifferent embodiments.

FIGS. 30-37 illustrate different tissue layer separation mechanisms thatinvolve a dissection probe in accordance with different embodiments.

FIG. 38 illustrates a probe with suction capability in accordance withsome embodiments.

FIG. 39 illustrates a conduit mechanism with suction capability inaccordance with some embodiments.

FIG. 40 illustrates a conduit mechanism that includes a stitchingmechanism in accordance with some embodiments.

FIG. 41 illustrates a lip grabbing mechanism in accordance with someembodiments.

FIG. 42 illustrates a conduit mechanism that includes suction capabilityin accordance with some embodiments.

FIG. 43 illustrates a dissection probe with an actuatable portion inaccordance with some embodiments.

FIG. 44 illustrates a dissection probe with an actuatable portion inaccordance with other embodiments.

FIG. 45 illustrates a dissection probe exiting from a guide member inaccordance with some embodiments.

FIG. 46 illustrates a dissection probe that is configured to oscillatein accordance with some embodiments.

FIG. 47 illustrates a dissection probe that is configured to move in alateral direction in accordance with some embodiments.

FIG. 48 illustrates a cage that may be used to create a pocket at avessel wall in accordance with some embodiments.

FIGS. 49a-49f illustrate different geometries for an expandablecomponent of a sub-intimal pocket creation mechanism in accordance withsome embodiments.

FIG. 50 illustrates another dissection probe having an actuatableportion in accordance with other embodiments.

FIG. 51 illustrates a cutting mechanism in accordance with someembodiments.

FIG. 52 illustrates another cutting mechanism in accordance with otherembodiments.

FIG. 53 illustrates a sub-intimal access mechanism that includes sharpedges in accordance with some embodiments.

FIGS. 54a-54c illustrate different geometries for an intimal separationmechanism in accordance with different embodiments.

FIGS. 55a-55c illustrate another autologous valve creation system, and amethod of using such system in accordance with other embodiments.

FIGS. 56a-56f illustrate another autologous valve creation system, and amethod of using such system in accordance with other embodiments.

DETAILED DESCRIPTION

Various embodiments are described hereinafter with reference to thefigures. It should be noted that the figures are not drawn to scale andthat elements of similar structures or functions are represented by likereference numerals throughout the figures. It should also be noted thatthe figures are only intended to facilitate the description of theembodiments. They are not intended as an exhaustive description of theinvention or as a limitation on the scope of the invention. In addition,an illustrated embodiment needs not have all the aspects or advantagesshown. An aspect or an advantage described in conjunction with aparticular embodiment is not necessarily limited to that embodiment andcan be practiced in any other embodiments even if not so illustrated.

FIGS. 1-6 illustrate components of a valve creation system in accordancewith some embodiments. The valve creation system includes a conduitmechanism 2 (FIGS. 1, 2), a sub-intimal access mechanism 18 (FIGS. 3a,3b ), and a sub-intimal pocket creation mechanism 32 (FIGS. 4a, 4b ). Insome embodiments, the sub-intimal pocket creation mechanism 32 mayoptionally include an intimal separation mechanism 46 (FIGS. 5a, 5b ).Also, in some embodiments, the sub-intimal pocket creation mechanism 32may optionally include a valve securement mechanism 48 (FIG. 6).

FIG. 1 illustrates a conduit mechanism 2 in accordance with someembodiments. As used in this specification, the term “conduit mechanism”or similar terms refer to any device that provides a conduit, channel,or lumen for housing and/or delivering a component or a substance. Theconduit mechanism 2 serves as a platform to support other devicecomponents, which can be inserted percutaneously into bodily lumen(s).The conduit mechanism 2 includes an elongated tube 3 with a proximal end4 and a distal end 5. The conduit mechanism 2 has an internal lumen 6,which extends from the proximal end 4 to the distal end 5 of theelongated tube 3, terminating at a sideway facing exit port 7 near, butsome small distance (e.g. 2 mm-10 mm) away from, the distal end 5 of theelongated tube 3. The conduit mechanism 2 also includes a distal exitport 8 located at the distal most tip of the elongated tube 3, whereinthe port 8 is in fluid communication with the internal lumen 6.

The conduit mechanism 2 also includes an angling mechanism 11. In thisembodiment, the angling mechanism 11 takes the form of a wire 12connected with a mechanical bond 13 to the distal-most end of theinternal lumen 6 of the conduit 2. In this embodiment, the anglingmechanism 11 extends through the internal lumen 6 and past the proximalend 4 of the conduit 2. In this embodiment, the stiffness of theelongated tube 3 is lower at the distal end than at the proximal end sothat when the wire 12 of the angling mechanism 11 is put into tension bythe user at the proximal end, the elongated tube forms a curvature 14near its distal end. Anyone skilled in the art of steerable cathetersshould understand how this mechanism can be used to create a curvaturefor the elongated tube 3. This curvature will allow tools to be passedthrough the sideway facing exit port 7 to take a non-parallel anglerelative to the lumen wall, facilitating autologous valve creation. FIG.1 depicts the conduit mechanism 2 in a straight orientation beforeactuation of the angling mechanism 11, while FIG. 2 depicts the conduitmechanism 2 in a curved orientation due to the actuation of the anglingmechanism 11.

In the illustrated embodiments, the conduit mechanism 2 also includes awall-tensioning mechanism 15. As used in this specification, the term“wall-tensioning mechanism” or similar terms refer to any device that isconfigured to apply tension at a wall of a vessel. The wall-tensioningmechanism 15 includes a sideway-facing, inflatable, compliant balloon 16of nearly cylindrical shape. The balloon 16 is coupled to the elongatedtube 3 near the distal end 5 of the elongated tube 3. The balloon is influid communication with an inflation lumen 17, which communicates withan inflation port at the proximal end 4 of the elongated tube 3. Theinflatable balloon 16 can be inflated to multiple diameters depending onthe quantity and pressure of inflation fluid supplied through theinflation lumen 17. FIG. 1 depicts a non-actuated wall-tensioningmechanism 15 with a deflated balloon 16, while FIG. 2 depicts thewall-tensioning mechanism 15 in its actuated orientation with aninflated balloon 16. The balloon 16 is configured (e.g., sized, shaped,etc.) to be placed in a vessel. When expanded, the balloon 16 applies atension at the wall of the vessel.

FIG. 3a depicts a sub-intimal access mechanism 18 in accordance withsome embodiments. As used in this specification, the term “sub-intimalaccess mechanism” or similar terms refer to any device, wherein at leasta portion of which is configured to be placed inside a wall of a vessel.The sub-intimal access mechanism 18 may be used with the conduitmechanism 2 of FIGS. 1 and 2. In particular, the sub-intimal accessmechanism 18 may be introduced through the lumen 6 of the conduitmechanism 2, and out of the sideway facing exit port 7.

In the illustrated embodiments, the sub-intimal access mechanism 18includes an elongated member 19 with a proximal end 20, a guide member100 having a closed blunt distal end 21, an internal lumen 22, and atissue engagement mechanism 23 extending from the elongated tube 19 at alocation a small distance (e.g. 2 mm-8 mm) proximal to the closed bluntdistal end 21. In this depiction, the tissue engagement mechanism 23includes a tubular structure 101 with a lumen 24 in fluid communicationwith the main lumen 22 of the sub-intimal access mechanism 18. There istherefore fluid communication from the proximal end 20 of thesub-intimal access mechanism 18 through the entire length of the mainlumen 22 of the sub-intimal access mechanism 18, into the lumen 24 ofthe tissue engagement mechanism 23, terminating distally at a forwardfacing exit port 25. In some embodiments, the tissue engagementmechanism 23 forms a relative angle with the elongated tube 19 of thesub-intimal access mechanism 18. The intersection of the tissueengagement mechanism 23 and the body of the elongated tube 19 creates abottoming-out mechanism 26, in the form of an elbow joint. In someembodiments, the tissue engagement mechanism 23 may be attached to theelongated tube 19. In other embodiments, the tissue engagement mechanism23 and the elongated tube 19 may be formed together in an unityconfiguration. For example, the tissue engagement mechanism 23 may be apart of the elongated tube 19. The tissue engagement mechanism 23 has asharpened tip 27, to facilitate penetration of an interior wall of ablood vessel. The angular orientation of the bevel of the sharpened tip27 is such that the distal most point of the bevel is oriented furthestaway from a longitudinal axis 102 of the sub-intimal access mechanism18. In particular, the distal profile of the tip 27 tapers proximallyfrom a first side 104 to a second side 106, wherein the first side 104is further away from the axis 102 than the second side 106. Suchconfiguration is advantageous because it allows the tip 27 to penetrateinto the vessel wall more easily.

The sub-intimal access mechanism 18 also includes a tissue layerseparation mechanism 28. As used in this specification, the term “tissuelayer separation mechanism” or similar terms refer to any mechanism thatis capable of separating tissue (e.g., dissecting tissue). The tissuelayer separation mechanism 28 includes a pressurized source offluoroscopic contrast agent 10, and a tissue layer separation actuator29. FIG. 3a depicts the tissue layer separation mechanism 28 prior toactuation, at which point the pressurized source of fluoroscopiccontrast agent 10 exists at the proximal end 20 of the sub-intimalaccess mechanism 18. FIG. 3b depicts the utilization of the tissue layerseparation mechanism 28 during actuation, at which point the pressurizedsource of fluoroscopic contrast agent 10 is forced through the mainlumen 22 of the sub-intimal access mechanism 18, and through the lumen24 of the tissue engagement mechanism 23, until it exits out of theforward facing exit port 25 as a high pressurized stream 30. The tissuelayer separation actuator 29 is a manually controlled piston mechanismor syringe. The stream of high-pressure fluid 30 can be used to separatelayers of a wall of a vessel by forcing its way between tissue layers,creating a semi-controlled hydrodissection (not depicted here). In someembodiments, the bolus of high-pressure fluid that that is expelled intothe inter-layer dissection plane in the vessel is sustained for 3-4seconds. In the illustrated embodiments, the fluid stream 30 provides afluid pressure inside the vessel wall that is sufficient to dissecttissue in the vessel wall, but insufficient to puncture through the wallof the vessel. The fluid stream 30 may have a fluid pressure anywherefrom 100 mmhg to 1000 mmhg. Also, in some embodiments, the fluid stream30 may be in pulses.

In some embodiments, the agent 10 may be a contrast agent, which may beimaged using an imaging device, such as a fluosorcopic device. Thisallows the position of the device 18 to be determined, and the fluidpath of the agent 10 to be visualized during delivery of the agent 10.This also allows the progress of the separation of the tissue layers inthe vessel to be monitored.

The distal tip 21 of the guide member 100 is configured to be placed ona surface at an interior wall of the vessel to thereby guide thepositioning (e.g., orientation) of the tip 27 relative to the vesselwall surface. In some cases, pressure may be applied to the vessel wallsurface by pushing the blunt tip 21 distally, which will apply tensionto the wall surface, and/or change an orientation of the wallsurface—either or both of which will allow the tip 27 to more easilypenetrate into the wall of the vessel.

In some embodiments, the tissue layer separation mechanism 28 isconfigured to dissect tissue in the wall of the vessel to create apocket inside the wall of the vessel having a size that is sufficient toform a flap at the vessel wall. In such cases, the fluid stream 30functions as a sub0intimal pocket creation mechanism. In otherembodiments, the tissue layer separation mechanism 28 is configured todeliver the fluid stream 30 to create an initial lumen in the wall ofthe vessel, and another device may be placed in the lumen to expand thesize of the lumen to create a pocket that is large enough to form a flapat the vessel wall. FIG. 4a depicts a sub-intimal pocket creationmechanism 32 in accordance with some embodiments. As used in thisspecification, the term “sub-intimal pocket creation mechanism” orsimilar terms refer to any mechanism that is configured to create apocket inside a wall of a vessel. The sub-intimal pocket creationmechanism 32 has an elongated member 33, with a proximal end 34, ablunt, tapered distal end 35, and a contrast lumen 36, which extendsfrom the proximal end 34 to a contrast exit port 37 at the distal end 35of the mechanism 32. The sub-intimal pocket creation mechanism 32 alsoincludes an inflatable, compliant pocket creation balloon 38, a ballooninflation lumen 39, and an inflation port 40, which connects the ballooninflation lumen 39 to the pocket creation balloon 38. In the illustratedembodiments, the pocket creation balloon 38 is bonded to the outersurface 33 of the sub-intimal pocket creation mechanism 32 to form anair-tight seal.

FIG. 4b depicts a configuration of the mechanism 32, in which the pocketcreation balloon 38 is inflated. In the illustrated embodiments, theinflated balloon 38 takes an asymmetric shape upon inflation through theinflation lumen 39, which inflates sideways off of the outer surface ofthe sub-intimal pocket creation mechanism 32. The pocket creationballoon's largest diameter 41 is some distance closer to the proximalend 42 of the balloon than to the distal end 43 of the balloon. Theballoon has a curved distal taper 44 and a curved proximal taper 45, theproximal one being more abrupt. In this embodiment, the sub-intimalpocket mechanism 32 is sized appropriately in its deflated orientationsuch that it has dimensional clearance through the main lumen 22 of thesub-intimal access mechanism 18, the narrow lumen 24 of the tissueengagement mechanism 23, as well as the forward facing exit port 25.

In some embodiments, the sub-intimal pocket mechanism 32 may optionallyfurther include an intimal separation mechanism 46 that is configured toincrease a size of an opening at a surface of a vessel wall (FIG. 5a ).As used in this specification, the term “intimal separation mechanism”or similar terms refer to a mechanism for finalizing intimal separationat the top lip of the valve (such as, a mechanism for providing adesired width at the top lip of a flap). In this embodiment, the intimalseparation mechanism 46 includes a backward facing cutting mechanism 47,depicted in this embodiment as a thin wire. The cutting mechanism 47 isbonded to the surface 33 of the elongated member 33, just proximal tothe pocket creation balloon 38. In this embodiment, the cuttingmechanism 47 is bonded such that expansion of the pocket creationballoon 38 will move the cutting mechanism 47 into its operativeposition, and will force the cutting mechanism 47 into contact withtissue. FIG. 5b shows a depiction of the intimal separation mechanism46, in which the cutting mechanism 47 assumes an expanded shape uponinflation of the pocket creation balloon 38. In other embodiments,instead of being secured to the elongated member 33, the cuttingmechanism 47 may be secured to the balloon 38. Also, in any of theembodiments described herein, the cutting mechanism 47 may include aplurality of sharp particles that is disposed on the surface of theballoon 38.

In some embodiments, the sub-intimal pocket mechanism 32 may optionallyfurther include a channel for delivering a valve securement mechanism,wherein the valve securement mechanism is configured to secure a flapagainst a wall of a vessel. FIG. 6a illustrates a channel 49 locatedwithin the elongated member 33 of the mechanism 32, which is fordelivering a valve securement mechanism. FIG. 6b depicts a valvesecurement mechanism 48 in accordance with some embodiments,particularly showing the valve securement mechanism 48 being deliveredinside the channel 49. FIG. 6d depicts a more detailed view of thedistal end 53 of the securement mechanism 48, which is comprised of asharp puncturing member 54 at the leading end, two nitinol distal cliparms 55, two nitinol proximal clip arms 56, a constraining sheath 57,and a detachment joint 58, which is located at the interface between thesecurement delivery system 51 and the securement mechanism distal tip53. In this depiction, the detachment joint 58 is shown as a notch inthe wire. Returning to FIG. 6b , which depicts the securement deliverysystem 51 as a wire, and an actuation mechanism 52, depicted as a springand latch system. In the illustrated embodiments, the channel 49 extendsfrom the proximal end of the sub-intimal pocket creation mechanism 32 toan angled side port 50, through which valve securement will beaccomplished. FIG. 6c depicts the valve securement mechanism 48 in itsinitial stage of deployment, in which the delivery system 51 has movedforward pushing the securement mechanism distal tip 53 out of the angledside port 50 by a short distance. FIG. 6e depicts the valve securementmechanism 48 in its second stage of actuation, as a result of activationof the actuation mechanism 52. In this embodiment, the activation of theactuation mechanism 52 occurs after inflation of the pocket creationballoon 38. The delivery system has moved forward to its maximumdistance, pushing the securement mechanism distal tip 53 to a distancefrom the elongated member 33 slightly exceeding that of the outer mostportion of the inflated pocket creation balloon 38. FIG. 6f depicts thevalve securement mechanism 48 in its third stage of actuation, in anorientation in which the constraining sheath 57 has been retractedenough to allow the distal clip arms 55 to spring outward into anorientation perpendicular to the axis of the delivery system 51 as aresult of their shape memory characteristics. The forth stage ofactuation is accomplished when the constraining sheath 57 is retractedfurther to allow the proximal clip arms 56 to spring outward into aorientation perpendicular to the axis of the delivery system 51 as aresult of their shape memory characteristics. FIG. 6g depicts the valvesecurement mechanism 48 in its fifth and final stage of actuation. Afterthe valve securement mechanism 48 has been deployed to secure a flapagainst a vessel wall, the entire securement mechanism delivery system51 is retracted forcing the securement mechanism distal tip 53 to detachfrom the securement mechanism delivery system 51 at the detachment joint58. The detachment joint 58 is intentionally built to fail in tension atthat location, so that the securement mechanism distal tip 53 is leftbehind upon retraction of the securement mechanism delivery system 51.In this embodiment, the securement mechanism distal tip 53 takes thefinal orientation of an “H-tag”. In other embodiments, the securementmechanism distal tip 53 may have other configurations (e.g., shapes).For example, in other embodiments, the securement mechanism may includeone or more tines having different deployed shapes. Also, in otherembodiments, instead of the above configurations, the securementmechanism 48 may be tissue glue that is deployed out of the channel 49,or another channel that is at a different device. The tissue glue isused to secure a flap against a vessel wall.

FIGS. 7-12 depict a method of using the above-described devices withinthe context of a percutaneous valve creation procedure. The describedfunctionality is by no means intended to be descriptive of all possibleuses of the devices. It should be noted that one or moreacts/functionalities may be omitted for certain procedural situations.

FIGS. 7-12 portray the devices being used within a bodily lumen 59 of avessel. For simplicity, the bodily lumen is shown with an inner layer60, and an outer layer 61. In many bodily lumens, such as the vein, thelumen wall is composed of three layers: the intima, media, andadventitia. In the following representations, the inner layer 60 mayrepresent the intima and the media combined, while the outer layer 61may represent the adventitia. Alternatively, in some embodiments ofvalve creation, the inner layer 60 may represent the intima, while theouter layer 61 may represent the media and the adventitia combined. Instill further embodiments, both the inner layer 60 and the outer layer61 may include the media.

FIG. 7 depicts the conduit mechanism 2 of FIG. 1, which has beeninserted percutanesously and delivered to the valve creation site 62within a bodily lumen 59, from the retrograde direction. In someembodiments, the user of the device may inject a fluoroscopic contrastagent 10 through the distal exit port of the conduit mechanism 8, sothat fluoroscopic visualization may be utilized to view the conduitmechanism 2. This may allow the user to determine the position of theconduit mechanism 2 relative to the valve creation site 62.

FIG. 8a depicts the conduit mechanism 2, in which the wall-tensioningmechanism 15 has been actuated. In this depiction, the main functionalcomponent of the wall-tensioning mechanism 15 is an inflatable compliantballoon 16, which extends perpendicularly from the surface 3 of theconduit mechanism 2 to the inner wall 60 of the bodily lumen 59. Theballoon is inflated through the inflation lumen 17 incrementally until aparticular pressure is measured which corresponds with proper lumen walldilation.

FIG. 8b depicts the conduit mechanism 2, in which the angling mechanism11 has been actuated. In this depiction, the main functional componentof the angling mechanism 11 is a wire 12, which is attached to amechanical bond 13 to the distal-most end of the internal lumen 6 of theconduit mechanism 2. In this depiction, the wire 12 has been tensionedfrom the proximal end, which forces the distal end 5 of the conduitmechanism 2, into a bent orientation. With the wall-tensioning mechanism15 actuated, the catheter surface 3 and the inflated balloon 16 are inflush contact with the inner lumen wall 60, and thus transfer theircurved orientation to the bodily lumen 59 itself. In this way, theangling mechanism 11, forces the wall of the vessel to bend. In theillustrated embodiments, the majority of the curvature of the conduitmechanism 2 occurs at or distal to the sideways facing exit port 7. Thisconfiguration is advantageous because it allows a tool passing out ofthe sideways facing exit port 7 to form a non-parallel angle with thewall of the vessel.

FIGS. 9a-9b depict the sub-intimal access mechanism 18 located in theconduit mechanism 2, and being deployed therefrom. FIG. 9a depicts thesub-intimal access mechanism 18 during actuation as it exits thesideways facing exit port 7, as a result of advancement from theproximal end of the conduit 4. Due to the curvature of the conduitdistal to the sideways facing exit port 7, the sub-intimal accessmechanism 18 exits the conduit at a non-parallel angle relative to theinner lumen wall 60. The guide member 100 is pressed against the vesselsurface to guide the positioning of the tissue engagement mechanism 23.For example, the mechanism 23 may be tilted about the contact pointbetween the guide member 100 and the vessel wall. Thus, the guide member100 allows the mechanism 23 to enter the vessel wall at a desired angle.In some cases, the guide member 100 also provides some tension at thevessel wall surface (i.e., in addition to that already provided by theballoon 16). FIG. 9b depicts the sub-intimal access mechanism 18 afterit has been advanced fully and has engaged the inner lumen wall 60. Inthe illustrated embodiments, the tissue engagement mechanism 23penetrates the vessel wall, and is advanced until vessel tissue abutsagainst a stopper (e.g., the region where the proximal end of the tissueengagement mechanism 23 meets the guide member 100). Full engagementoccurs after the tissue engagement mechanism 23 penetrates the vesselwall, and when the tissue between the guide member 100 and the mechanism23 meets the elbow joint of the bottoming-out mechanism 26 (thestopper). Upon full tissue engagement, the forward facing exit port 25of the tissue engagement mechanism 23 rests completely within the lumenwall.

FIG. 10 depicts the tissue layer separation mechanism 28 being used atthe valve creation site 62. After the tip 27 of the tissue engagementmechanism 23 has been placed inside the wall of the vessel, thepressurized source of fluoroscopic contrast agent 10 is forced throughthe main lumen 22 of the sub-intimal access mechanism 18, and throughthe narrow lumen 24 of the tissue engagement mechanism 23, until itexits out of the forward facing exit port 25 as a high pressure stream30. This stream of high-pressure fluid 30 acts to atraumaticallyseparate the inner layer 60 from the outer layer 61 of the bodily lumen59 at the valve creation site 62 by physically breaking interlayer bondsupon injection, creating a semi-controlled, inter-layer dissection plane31. In some embodiments, the pressure of the stream 30 is sustaineduntil the dissection plane 31 with a certain length has been created. Inother embodiments, the stream 30 may be delivered in pulses. Also, inother embodiments, the pressure of the stream 30 may be adjusted (e.g.,increased) as the length of the dissection plane 31 is increasing insize. High-pressure fluid dissection offers advantages over blundmechanical dissection with a stiff probe. The dissection force impartedwithin the vessel wall is spread out over the internal surface area ofthe dissection pocket, and thus imparts less force in any one locationthan would a solid probe (or a solid device). Additionally, with fluiddissection, tissue separation automatically occurs along a plane ofleast-resistance, which may allow dissection to take place at a lowerpressure (e.g., compared to using a solid device).

Because a fluoroscopic contrast agent 10 is used in tissue layerseparation in this embodiment, the user will have the opportunity tovisualize the effect of the fluid delivery on the tissue usingfluoroscopic visualization techniques. In particular, throughfluoroscopic visualization technique, the user may view the progress ofthe tissue dissection within the wall of the vessel. The fluoroscopicvisualization technique also allows a user to determine if thedissection plane 31 is getting too close to the exterior surface of thevessel wall. In such cases, the user may determine that there is apotential that the vessel wall may be punctured (by the fluid)therethrough, and may stop the process. Additionally, this visualizationtechnique allows the user to evaluate the depth and shape of the newlycreated inter-layer plane 31 to determine if the tissue layer separationmechanism 28 needs to be actuated again. This process may be repeatedindefinitely until a proper tissue layer separation has occurred, whichallows for continuation of the procedure.

FIG. 11a depicts that the sub-intimal pocket creation mechanism 32 isadvanced into the inter-layer plane 31. Following proper separation oftissue layers using the tissue layer separation mechanism 28, thesub-intimal pocket creation mechanism 32 is advanced through the mainlumen 22 of the sub-intimal access mechanism 18, into the narrow lumen24 of the tissue engagement mechanism 23, and out of the forward facingexit port 25. As depicted in FIG. 11a , the sub-intimal pocket creationmechanism 32 is advanced out of the forward facing exit port 25 of thetissue engagement mechanism 23, and into the newly created inter-layerplane 31 that now exists between the inner layer 60 and the outer layer61 of the lumen wall. The sub-intimal pocket creation mechanism 32 isadvanced far enough such that the proximal most portion of the deflatedpocket creation balloon 38 is at least within the inter-layer plane 31.

FIG. 11b depicts that the sub-intimal access mechanism 18 along with theconduit mechanism 2 has been removed, leaving only the sub-intimalpocket creation mechanism 32 behind, within the inter layer plane 31previously created.

FIG. 11c depicts the first stage of actuation of the valve securementmechanism 48, which occurs prior to the sub-intimal pocket creation.Once the sub-intimal pocket creation mechanism 32 is advancedsufficiently into the newly created inter-layer plane 31, the securementmechanism delivery system 51 is advanced forward a small amount pushingthe securement mechanism distal tip 53 out of the angled side port 50.Because of its sharp puncturing member 54, and the position and angularorientation of the angled side port 50 with respect to the newlyseparated inner tissue flap 63, the securement mechanism distal tip 53punctures through the inner tissue layer flap 63 from its inter-layerplane 31 side, and emerges into the inside of the bodily lumen 59. Thevalve securement mechanism maintains control of the inner tissue layerflap 63 throughout the completion of sub-intimal pocket creation, priorto completing the subsequent stages of the valve securement.

FIG. 11d depicts the sub-intimal pocket creation mechanism 32 beingutilized. Following the first stage of actuation of the valve securementmechanism 48, and with the entire deflated pocket creation balloon 38immersed within the inter-layer plane 31, the pocket creation balloon 38is inflated through the inflation lumen 39, prompting expansion to itsasymmetric shape. As depicted, the balloon expansion within theinter-layer plane 31 acts to further separate the inner layer tissueflap 63 from the outer layer 61 of the lumen wall, until a fullsub-intimal pocket 64 has been created between the layers 61, 62. Thegeometry of this sub-intimal pocket 64 is determined by the shape, sizeand position of the pocket creation balloon 38 upon inflation. At thispoint, there exists a narrow inlet 65 in the top of the sub-intimalpocket with a circular shape just large enough to allow for dimensionalclearance of the sub-intimal pocket creation mechanism 32. This inletwas created originally when the tissue engagement mechanism 23penetrates through the vessel surface and into a wall of the vessel.

FIG. 11e depicts the second stage of actuation of the valve securementmechanism 48 immediately following, or simultaneously with, thesub-intimal pocket creation. After/during inflation of the pocketcreation balloon 38, the securement mechanism delivery system 51 isfurther advanced, which acts to push the securement mechanism distal tip53 through both the inner tissue layer 60 b and the outer tissue layer61 b at the opposing side of the lumen, so that it rests in theextra-luminal space 66.

FIG. 11f depicts the third stage of actuation of the valve securementmechanism 48. Once the securement mechanism distal tip 53 has beenadvanced into the extra-luminal space 66, the constraining sheath 57(not depicted) is retracted a small amount, allowing the distal cliparms 55 to spring outward into an orientation perpendicular to the axisof the delivery system 51 as a result of their shape memorycharacteristics. This clip orientation restricts the distal tip 53 frominadvertently disengaging in the backwards direction from the tissuelayers through which it has been advanced.

FIG. 11g depicts the forth stage of actuation of the valve securementmechanism 48. The constraining sheath 57 (not depicted) is retractedfurther to allow the proximal clip arms 56 to spring outward into aorientation perpendicular to the axis of the delivery system 51 as aresult of their shape memory characteristics. Once expanded, theproximal clip arms 56 rest within the sub-intimal pocket 64. At thispoint the inner tissue layer 60 a from one side of the lumen, the innertissue layer 60 b from the other side of the lumen, and the outer tissuelayer 61 b from the other side of the lumen, are constrained between theproximal clip arms 56 and the distal clip arms 55. Thus, the clipsecures the flap formed from a first wall portion of a vessel relativeto a second wall portion that is opposite from the first wall portion.

FIG. 11h depicts the fifth and final stage of actuation of the valvesecurement mechanism 48. The entire securement mechanism delivery system51 is retracted forcing the securement mechanism distal tip 53 to detachfrom the securement mechanism delivery system 51 at the detachment joint58. In this way, the securement mechanism distal tip 53 is left behind,depicted in this embodiment as an “H-tag” upon detachment. This formacts to prevent the newly separated inner tissue layer 60 a fromassuming its natural orientation against the outer tissue layer 61 a,thus preventing it from biologically re-adhering in its originallocation. The delivery system 51 and the constraining sheath 57 arecompletely removed from the anatomy through the securement tool lumen 49of the sub-intimal pocket creation mechanism 32. In other embodiments,instead of relying on tension to break the detachment joint 58, thejoint 58 may be disintegratable in response to a current or heat appliedtherethrough.

FIG. 11i depicts a cross-section view of the bodily lumen 59 at thelongitudinal position of the pocket creation balloon's 38 largestdiameter (denoted A-A on FIG. 11h ). A large percentage of the area ofthe bodily lumen is occupied by the newly created inter layer pocket 64.

FIG. 11j depicts a cross-section view of the bodily lumen 59 at thelongitudinal position just proximal on the sub-intimal pocket creationmechanism 32 to the pocket creation balloon 38 (denoted B-B on FIG. 11h). At this location, the narrow inlet 65 at the top of the inner tissuelayer flap 63 is seen, and is a much smaller opening than the fullextent of the pocket diameter at a more distal location.

FIGS. 12a-12b depict the intimal separation mechanism 46 being utilized.The act of inflation of the pocket creation balloon 38 during thecreation of a sub-intimal pocket 64 actuates the backward facing cuttingmechanism 47 to its expanded orientation (depicted in FIG. 11d ). Asdepicted in FIG. 12a , the sub-intimal pocket creation mechanism 46 isremoved from the newly created sub-intimal pocket 64 while the pocketcreation balloon 38 is still inflated. The proximal movement of themechanism 46 causes the cutting mechanism 47 to cut tissue next to theopening 65 at one end of the flap 63, thereby increasing the size of theopening 65. This provides the flap 63 with the desired width. It shouldbe noted that as the inflated balloon 38 of the mechanism 46 is removedproximally out of the inlet 65, counter-tension is created at the vesselwall, which allows the backward facing cutting mechanism 47 to make aclean, consistent cut at the vessel wall along a path (e.g., a curvedpath) according to the shape of the expanded backward facing cuttingmechanism 47. In the embodiment depicted, the circumferential angle(measured along the circumference of the vessel) of the inner tissuelayer separation is over 180° (e.g., 180°+10°), and the cut is nearhorizontal (i.e., the direction of the cut is approximatelyperpendicular to the longitudinal axis of the vessel). In otherembodiments, the cut may not be horizontal. Also, in other embodiments,the length of the cut made by the cutting mechanism 47 may be less than180°. The separation of the inner tissue layer flap 63 finalizes the toplip of the newly created autologous valve 67. At this point, the pocketcreation balloon 38 is deflated, and the autologous valve creation hasbeen accomplished. FIG. 12b depicts a cross-sectional view of the fullycreated autologous valve 67 at the longitudinal plane located directlyproximal to the securement of the inner tissue layer flap 63 (denotedB-B on FIG. 11h ), after the device has been fully removed.

After the valve 67 is created, the user may visualize the effect ofautologous valve creation using fluoroscopic visualization techniques.Contrast agent 10 can be injected through the forward facing exit port25 of the pocket-creation mechanism 32 (or through another fluiddelivery device) at any appropriate time during the procedure. This toolwill be especially useful after valve creation has been accomplished. Inthis case, the user may first deflate the pocket creation balloon 38 tofacilitate placement of the forward facing exit port 25 in the newlycreated sub-intimal pocket 64. Standard techniques—including manualpumping of the calf muscle—can be used to force blood flow through theautologous valve 67 for evaluation. Once visualization confirms thatautologous valve 67 is functioning properly, the device is removed fromthe bodily lumen.

Upon creation of the autologous valve 67 depicted in FIG. 12b , aspecific valve geometry is created. FIG. 13a-13e depict many aspects ofone specific preferred valve geometry that could be created in a bodilylumen 59 using embodiments of the devices described herein. FIG. 13adepicts a cross-sectional view of a monocuspid valve geometry. A leaflet68, composed of the inner layer tissue flap 63 is shown protruding fromone lumen wall and extending toward and up to the lumen wall at theopposing side of the lumen, creating a mono-directional autologous valve67. In this embodiment, the valve cusp 69 takes a curved shape, whichallows for blood circulation 70, preventing stagnation. FIG. 13b depictsdifferent shapes of the sub-intimal pocket 64 created between theleaflet 68 and the luminal wall from where the flap was dissected. Thispocket 64 takes the shape of an up-side-down triangular extrusion with acurved side, which matches the lumen wall. FIG. 13c depicts approximaterelative dimensions for the height 800 and circumferential width 71 of avalve geometry in accordance with some embodiments. The height 70 of theleaflet 68 (at its tallest point) is greater than the inner diameter ofthe lumen 72, and the circumferential width 71 of the leaflet 68 isslightly greater than 180°, as similarly discussed. As describedpreviously, a securement mechanism 48 may be used to secure the flap ofthe valve to a vessel wall in accordance with some embodiments. FIG. 13ddepicts the location of securement 73 to be longitudinally lower thanthe line of detachment 74 of the inner tissue layer 60 from the rest ofthe lumen wall (see arrow in figure representing the offset). FIG. 13edepicts the effect of this securement location during the closing cycleof the autologous valve 67, which results in the lateral movement ofredundant tissue of the leaflet 68 so that it may freely occlude againstthe opposing lumen wall in the closed valve orientation, without havingto over-stretch the tissue of the leaflet 68.

It should be noted that the system and method for creating a valveinside the vessel is not limited to the embodiments describedpreviously. In other embodiments, the system may have differentconfigurations. Also, in other embodiments, the method may be carriedout using different devices and/or techniques.

In the above embodiments, the device has been described as utilizingcontrast solution and fluoroscopic techniques for \visualization. Inother embodiments, the device may utilize an external ultrasound deviceto facilitate navigation of the conduit mechanism 2 to the desiredtarget location, to monitor progress of the valve creation procedure,and/or to confirm that a desired valve has been created. FIG. 14 anultrasound probe 140 with a specific shape to conform to the externalanatomy of the thigh 142 or other external anatomical locations. In suchembodiments, if used in the venous system, the depth of penetration maybe programmed for focus on the deep vein anatomy of the average patientwith deep vein insufficiency, particularly for superficial femoral vein,the popliteal vein, the common femoral vein, or any of other veins ofthe deep venous system. In the embodiment depicted, the front end of theprobe has a fixturing mechanism 144 so that upon actuation the probe canremain static with respect to the leg. In this embodiment, the fixturingmechanism includes a suction cup that can be actuated to create alow-pressure chamber by sealing off the chamber while removing some airwithin the chamber. Such a mechanism can be easily reversed to decouplethe device from the patient when necessary. In another embodiment, thefixturing mechanism 144 may be a strap that wraps around the patientsleg, and can be tightened or loosened with a latching mechanisms forsemi-permanent clamping. In some such embodiments, the ultrasound probe140 has a paired video output on the probe itself, allowing thephysician to visualize the underlying vein by looking directly at thepatient's leg.

In a previous embodiment, the device 140 was described as an ultrasounddevice placed external to the patient for achieving visualization. Inother embodiments, the device 140 may be another external imagingmodality. For example, in other embodiments, the visualization may beaccomplished with magnetic resonance imaging. In other embodiments, thevisualization may be accomplished with computed tomography scanning. Instill other embodiments, the visualization may be accomplished withoptical coherence tomography. In further embodiments, the visualizationmay be accomplished with intravascular ultrasound.

In other embodiments, the visualization may be achieved with othersensing technologies that help evaluate certain hemodynamic parameters,which aid in identifying the proper location for intervention or forassessing procedural success during and/or after the procedure. Suchmodalities may include device for measuring localized blood pressure,flow meters, pulse oximetry, or for performing other physicalexamination(s).

In other embodiments, the visualization may be achieved using a directvisualization technique. In one such embodiment, the interventional siteis evacuated of blood. For example, proximal and distal balloons may bedelivered into the vessel lumen, where they are inflated, and blood isevacuated through a port in the catheter between the two balloons. Inone such embodiment, the two balloons are housed on separate butparascoping catheters. In another such embodiment, the balloons are onthe same catheter. In some cases, the balloons utilized for evacuationof blood may also provide additional longitudinal countertension. Afterthe blood between the balloons is removed, a camera may then bedelivered in the vessel for viewing. In another embodiment, an externalwrap and turnakit system may be used to exsanguinate the leg of bloodprior to the procedure. In other embodiments, direct visualization isobtained without evacuating the site of blood, but by housing a camerawithin a balloon. The balloon can be inflated with a clear liquid orgas, and pushed against a luminal wall, allowing direct visualization ofthe wall and surrounding anatomy. In another embodiment, the camera canbe housed within a device having a clear solid surface which allows thecamera to view tissue therethrough. In one other embodiment, clear gasor liquid can be continuously introduced in front of the camera toensure continuous visualization through blood.

In other embodiments, direct visualization may be obtained with a camerapositioned within the sub-intimal access mechanism 18. In anothersimilar embodiment, the camera is located within the conduit mechanism 2directed toward the interventional site through the sideways facing exitport. In other embodiments, the camera may be mounted on a separateguide that can be fed at anytime through any of the previously describedlumens. In further embodiments, the camera may be housed in a completelyseparate guiding device, that may be introduced to the interventionalsite through the same or different incision point. For example, thevisualization device may be inserted percutaneously at a first incisionpoint to enter into the vessel lumen, and any of the valve creationdevices described herein may be inserted percutaneously at a secondincision point to enter into the same vessel lumen. The visualizationdevice and any of the devices described herein may be advanced insidethe vessel from opposite directions to reach the same target location.

In the above embodiments, the device has been described as utilizing atensioned wire bonded to the distal tip of the conduit mechanism 2 forthe angling mechanism 9. In other embodiments, as depicted in FIG. 15,the device may utilize a pre-formed conduit mechanism 2 with a curve atthe distal section 150. In this embodiment, the conduit is naturallycurved at the distal section 150, but may be straightened during accessof the bodily lumen if necessary by inserting a straight stiff stylet152 in the internal contrast lumen 6.

FIG. 16 depicts another embodiment, in which the angling mechanism 11 isembodied as a taper on one side of the conduit mechanism 2 atapproximately the same longitudinal and radial position of the sidewaysfacing exit port 7. Upon actuation of the wall-tensioning mechanism 15,the inner tissue layer 60 will conform to the tapered geometry, thusforming an angle relative to a longitudinal axis of the conduitmechanism 2. In such configuration, when the sub-intimal accessmechanism 18 exits through the port 7, the mechanism 18 will penetratesinto the inner tissue layer 60 at a desired angle relative to the tissuelayer 60.

FIG. 17 depicts another embodiment, in which the angling mechanism 11 isembodied as the sub-intimal access mechanism 18 itself, wherein themechanism 18 has a pre-formed shape achieved by making at least a partof the mechanism 18 using Nitinol or other material having shape-memorycharacteristic. In this embodiment, the sub-intimal access mechanism 18is shaped so that upon exiting the constraints of the conduit lumen 6through the sideways facing exit port 7, it takes its natural angledshape so that it penetrates the inner tissue layer 60 at a desired anglerelative to the layer 60. In this way, the sub-intimal access mechanism18 takes an appropriate angle with the inner tissue layer 60 uponexiting the sideways facing exit port 7.

FIG. 18 depicts another embodiment, in which the angling mechanism 11 isembodied as a curved stylet 160 which is introduced through anadditional lumen 162 in the conduit mechanism 2. Upon introduction,because the curved stylet 160 has sufficient stiffness to transfer thatcurvature to the conduit mechanism 2 and the vessel itself, the innertissue layer 60 of the vessel will be forced to curve along the surfaceof the conduit mechanism 2.

It should be noted that the wall-tensioning mechanism 15 is not limitedto the balloon 16 described previously, and that in alternateembodiments the wall-tensioning mechanism 13 may be implemented usingother device(s) and technique(s). FIG. 19 depicts one such embodiment,in which the wall-tensioning mechanism 15 is an expandable cage 170 madefrom shape-memory Nitinol attached to the side of the conduit mechanism2. Prior to actuation, a sheath 172 rests over the compressed Nitinolcage 170. To actuate the wall-tensioning mechanism 15, the sheath 172 isretracted such that the cage 170 assumes its shape memory expandedconfiguration.

In other embodiments of the wall-tensioning mechanism 15, the cage 170is made of Stainless Steel (or any of other suitable materials, such aspure metals, alloys, or shape memory polymers), and may be expanded withassistance from an expanding balloon.

In some embodiments described herein, the wall-tensioning mechanism 15is an expanding balloon 16 attached to the elongated member 3 of theconduit mechanism 2. In other embodiments, as depicted in FIG. 20,instead of a side-ways facing balloon 16 bonded to the surface of theconduit mechanism 2, a radially symmetric balloon is mounted to adelivery catheter 180, and the center of the balloon 16 is offset fromthe axis of the catheter 180. In such configuration, that expansion ofthe balloon 16 in one direction is constrained by the wall of theelongated member 3. In such embodiments, the balloon 16 is forced toexpand outward with a bias toward the interior vessel wall, offset fromthe longitudinal axis (e.g., central axis) of the main conduit mechanism2. In other embodiments, the balloon 16 may be made from a firstmaterial that is stiffer on one side (the side closer to the elongatedmember 3), and relatively less stiff on the opposite side (the sidefurther away from the elongated member 3). Such configuration allows theballoon 16 to expand to an asymmetric shape, or to a shape having acentral axis that is offset from the axis of the catheter 180.

FIG. 21 depicts another embodiment, in which a radially symmetricballoon 16 is attached to an independent balloon guide 190 with aninflation lumen of its own. This balloon guide 190 and balloon 16 ishoused within a balloon lumen 17 within the conduit mechanism 2. Theinflation lumen 7 is in fluid communication with the proximal end of theconduit mechanism 2. In this embodiment, there exists a sideways facingexit port 7 b in the conduit surface, at the same longitudinal positionas the balloon 16 itself, spanning a length of at least that of theballoon 16. Upon inflation of the balloon 16, the balloon 16 isconstrained on one side by the wall of the balloon lumen 17, but free toexpand out of the balloon side-port 17 b, which allows for outwardexpansion in a perpendicular direction to a longitudinal axis of theconduit mechanism 2. In other embodiments, the balloon 16 may have anasymmetric configuration. Also, in any of the embodiments describedherein, the balloon 16 may be compliant.

In any of the embodiments described herein, the balloon 16 may beconfigured to expand in a lateral direction, wherein the balloon 16 ismounted to the conduit mechanism 2 with its direction of expansion beingperpendicular to the longitudinal axis of the conduit mechanism 2. Insuch configuration, when the balloon 16 is inflated, it expandslaterally to dilate the vessel wall.

The sub-intimal access mechanism 18 is not limited to the embodimentsdescribed previously, and may have different configurations in differentembodiments. FIG. 22 depicts the sub-intimal access mechanism 18 havinga naturally curved, forward facing needle 200 with internal lumen 202,used to directly gain access into the sub-intimal space. The curvedneedle 200 takes a tight curve outward toward the vessel wall as itinitially exits from the port 7, but straightens out such that itbecomes parallel with the longitudinal axis of conduit mechanism 2 afterit has been further deployed into the wall of the vessel. In thisembodiment, the sub-intimal access mechanism 18 is advanced through themain lumen 6 of the conduit mechanism 2 until it approaches the sidewaysfacing exit port 7. The lack of constraint provided allows the curvedneedle 200 to take its natural shape described. It is then advancedfurther until it penetrates the inner tissue layer 60, which bottoms outwithin the cusp created between the sub-intimal access mechanism shaftand the conduit surface. At this point, a tissue layer separationmechanism, such as fluid, an expandable device, or both, may bedelivered out of the lumen 202 of the needle 200 to separate the layers60, 61.

FIG. 23 depicts another embodiment in which the sub-intimal accessmechanism 18 takes the form of a curved needle 200 used in a similar wayas the previous embodiment. The curved needle 200 takes a tight curveoutward toward the vessel wall as it is initially delivered out of theport 7 (top figure). As the needle 200 is further advanced distally, itcurves back slightly away from the layer 61 of the vessel wall (bottomfigure). This configuration allows the needle tip to first contact thetissue at an angle that is almost parallel (e.g., 0°±10°) to the vesselwall, then as the curved needle 200 is advanced so that its fullcurvature exits the sideways facing exit port 7, the needle tip beginsto change angle so that its tip is pointing towards the center of thevessel lumen. This embodiment allows for the curved needle 200 to gainaccess to the inter layer plane between the layers 60, 61, but thenhelps to prevent full perforation of the vessel wall by not allowing theneedle 200 to continue advancing distally towards the layer 61.

FIG. 24 depicts another embodiment, in which the sub-intimal accessmechanism 18 is a forward facing needle 210 with internal lumen 212,that is accelerated in a specific way in order to directly gain accessinto the sub-intimal space. In this embodiment, the needle 210 isaccelerated a fixed distance out of the sideways facing exit port 7 ofthe conduit mechanism 2. Upon exiting the conduit mechanism 2, theneedle 210 punctures the inner tissue layer 60 at a non-perpendicularangle to the vessel wall. The accelerated motion will help to preventvisco-elastic dynamic effects of the vessel wall, including recoil andrelaxation from recoil back toward the puncturing element. Thismechanism and method provides a safe way to get to a specific distancewithin the lumen wall, as there will be close to a one to onecorrespondence between the distance the needle 210 is extended and thedepth of penetration. Actuation of this forward motion may befacilitated by a spring mechanism on the proximal end of the device,much like the actuation mechanism 52 of the securement mechanism 48previously described. In this embodiment, the distal tip of the needle210 is advanced up to the interface between the inner tissue layer 60,and the outer tissue layer 61. Depth of penetration is controlled by amechanical stop 214 located some distance from the distal end of theneedle 210. The mechanical stop 214 is configured to abut against aprotrusion 216 at the conduit mechanism 2 to thereby stop theadvancement of the needle 210. The delivered needle 210 may be used tocarry out various functionalities as similarly described previously withreference to the tissue engagement mechanism 23.

FIG. 25a depicts another embodiment. In this embodiment, the sub-intimalaccess mechanism 18 is a needle 220 with an internal lumen 222 that isconfigured to exit out of the side port 7 at the conduit mechanism'sdistal end. The distal tip of this needle 220 is sharp. The needle 220is accelerated a fixed distance out of the sideways facing exit port 7of the conduit mechanism 2 and into the inner tissue layer at aperpendicular angle to the luminal wall. In this depiction, the sidewaysexit port 7 is circular rather than a long oval and is connected to aninternal delivery lumen 6 within the conduit mechanism 2. This deliverylumen 6 has a 90-degree curvature near the distal end of the conduitmechanism 2, which connects to the sideways facing exit port 7. Thedelivered needle 210 may be used to carry out various functionalities assimilarly described previously with reference to the tissue engagementmechanism 23.

FIGS. 25b-25c depict alternative embodiments, in which the needle 220 iscomprised of an internal lumen 222 in fluid communication with a port224 at the distal end. In these depictions, the needle tip is sharp butclosed, and the port 224 faces towards a direction that is approximatelyparallel (e.g., 0°±10°) to the vessel wall. Such configuration allowsthe fluid 30 exiting the needle 220 to travel at a direction that isapproximately parallel to the vessel wall to thereby dissect tissue inthe vessel wall.

In other embodiments of the sub-intimal access mechanism 18, a guidewiremay be used in place of a forward facing needle to penetrate the innertissue layer 60. In some cases, the guidewire may be configured toaccelerate distally to travel a fixed distance, as similarly describedpreviously with reference to the needle. In one such embodiment, theguidewire penetrates into the vessel wall at a non-parallel angle to thelumen wall. In another such embodiment, the guidewire penetrates intothe lumen wall at an angle that is perpendicular to the wall of thevessel. In these embodiments, a hollow tube (which may be considered tobe a part of the sub-intimal access mechanism 18, or a separate device)may be passed over the guidewire upon gaining access to the interfacebetween the inner tissue layer 60 and the outer tissue layer 61, untilit too rests in the inter-tissue plane. The delivered tube may be usedto carry out various functionalities as similarly described previouslywith reference to the tissue engagement mechanism 23.

In the above embodiments, the device has been described as having atissue engagement mechanism 23 (which may include a needle, or aguidewire) for penetrating into the wall of the vessel. FIGS. 26a-26bdepict an alternate embodiment, in which the sub-intimal accessmechanism 18 includes a curved blade 240, mounted on a rotary guide 242,which is free to rotate within the main lumen 6 of the conduit mechanism2. A sideways facing exit port 7, allows the blade 240 to periodicallyprotrude radially past the surface of the conduit mechanism 2. In thisway, through a certain range of angles of rotation, the blade 240 issafely constrained within the outer surface of the conduit mechanism 2,and therefore not in contact with the vessel wall, as depicted in FIG.26a . Conversely, through another certain range of angles of rotation,the blade 240 protrudes radially past the outer surface of the conduitmechanism 2, and thus contacting the wall of the vessel, as the conduitsurface itself is in contact with the vessel wall (due to the actuationof the wall-tensioning mechanism 15), as depicted in FIG. 26b . Once theblade 240 is rotationally actuated from the proximal end, an incision ismade in only the inner tissue layer 60, due to the fixed depth of cutprovided by the limited reach of the blade 240 from the sideways facingexit port 7. In these embodiments, a delivery device (e.g., a hollowguidewire, a needle, a probe, etc.) which functions as a deliverymechanism for the tissue layer separation mechanism (e.g., fluid,balloon, expandable device, etc.) can then be introduced through theincision created by the blade 240, by passing through the sidewaysfacing exit port 7. Henceforth, the valve creation procedure can becompleted in similar way as that described previously, with theexception that the blade 240 is used to accomplish the task of cuttingacross a portion of the inner wall layer 60 circumferentially to providea desired width for a flap. Thus, the intimal layer separation mechanism46 is not required in this embodiment for increasing a size of apreviously created opening to create a flap with a desired width.

The sub-intimal access mechanism 18 that includes the rotational blade240 may have different configurations in different embodiments. In onesuch embodiment, the blade 240 is linear instead of curved. In someembodiments, the blade 240 is supported by the rotary guide at somepoint along the shaft of the guide as opposed to at the distal end. Insome such embodiments, the rotary guide can be removed from the conduitlumen 6 when the blade 240 is rotated to point inward toward the lumen 6of the conduit mechanism 2. In other such embodiments, the rotary guideis longitudinally fixed but allowed to move laterally within the conduitlumen 6, effectively changing the axis of the blade rotation. In othersuch embodiments, the rotary guide is permanently fixed on the samerotational axis.

The previous embodiments were described with reference to usinghigh-pressure contrast solution 10 to separate the layers (i.e.hydrodissection). However, in any of the embodiments described herein,alternate embodiments of the tissue layer separation mechanism may beused. In other embodiments, saline may be used. In further embodiments,a fluid based anti-thrombogenic agent may be used. In still furtherembodiments, water or another fluid may be used.

In any of the embodiments described herein, a shorter period ofsustained hydrodissection may be used, in contrast to the 3-4 secondduration described previously. In one such embodiment, the bolus ofhydrodissection is sustained for a duration of 1-2 seconds. In anothersuch embodiment, the bolus of hydrodissection is sustained for afraction of a second.

A variety of embodiments have been described that utilizehydrodissection as the mechanism for tissue layer separation. In somesuch embodiments, hydrodissection is administered through the lumen 22of the sub-intimal access mechanism 18. In other embodiments,hydrodissection can be administered through a hollow guidewire, needleor probe inserted through a previously created opening at the inner wallof the vessel. The following schematics depict different forms andutilizations of hydrodissetor delivery mechanisms. As used in thisspecification, the term “hydrodissector delivery mechanism” or similarterms refer to the element that delivers pressurized fluid betweentissue layers for the purpose of tissue layer separation.

FIG. 27 depicts an embodiment of the hydrodissetor delivery mechanism250 of the tissue layer separation mechanism 18, which provides a volumeof high-pressure fluid at the point of sub-intimal access. After thefluid is delivered, the dydrodissector delivery mechanism 250 isadvanced into the inter layer plane so that a second hydrodissection canbe performed to further separate the tissue layers. In this embodiment,such cycles of hydrodissection followed by hydrodissetor deliverymechanism 250 advancement may be repeated as many times as needed. Inother embodiments, the hydrodissetor delivery mechanism 250 is advancedsimultaneously during hydrodissection. In further embodiments, thehydrodissetor delivery mechanism 250 is rotated during advancement whileinjecting pressurized fluid out of the exit port(s) at the mechanism250. The hydrodissector delivery mechanism 250 may be any tubularstructure, such as that with lumen 24, or any of the needles describedherein.

FIGS. 28 and 29 depict other embodiments, in which the hydrodissetordelivery mechanism 250 contains multiple exit ports 260, which arestrategically placed such that the stream of pressurized fluid 30 isdirected along the intended direction of dissection to separate tissuelayers. FIG. 28 depicts an embodiment, in which the hydrodissetordelivery mechanism 250 is advanced lengthwise some distance into thesub-intimal space, close to parallel to the vessel wall. In thisembodiment, the hydro-dissector 250 contains multiple sideways facingexit ports 260 along the opposite longitudinal sides of thehydrodissetor delivery mechanism 250 (top figure). In other embodiments,the ports 260 may be located on one side of the hydrodissector deliverymechanism 250 (bottom figure). In the illustrated embodiments, the ports260 are oriented so that they face towards the inner tissue layer side60 (facing towards the center of the lumen). In this way, pressurizedfluid 30 is forced sideways to create a greater width of inter-layerpocket. Additionally, the ports facing the center of the vessel lumenhelp to peal the inner tissue layer 60 away from the outer tissue layer61. In any of the embodiments described herein, the hydrodissetordelivery mechanism 250 may optionally further contain forward facingexit port(s), which point in the direction of dissection.

FIG. 29 depicts an embodiment in which the previously described sidewaysfacing exit ports 260 are angled slightly in the direction of dissectionas opposed to being perpendicular to the longitudinal axis of thehydrodissector delivery mechanism 250.

In any of the embodiments described herein, a hydrodissection controlmechanism may be utilized to control the depth and width of tissueseparation created by the hydrodissector delivery mechanism 250. Thehydrodissection control mechanism regulates the flow-rate, flow-volume,flow duration, and/or pressure of flow of the hydrodissection fluid 10.These parameters can thus be tuned to create tissue separation atspecific distances from a specific exit port. In one such embodiment,such parameters are controlled on the proximal end with anelectronically incorporated valved system. In another such embodiment,such embodiments are regulated by a mechanical device near or at theexit ports 260. In some embodiments forward facing ports may havedifferent sizes than side ports to impart different flow-rates indifferent directions. This will help to control the width and depth ofthe dissection pockets separately. The same principal may apply to sideports 260 facing the intima, and flow-rates may be controlled forfunctional or safety reasons. In some cases, it may be more clinicallyor technically feasible to have a hydrodissection that only has theforce to dissect tissue in close proximity to the exit ports 260themselves. In such embodiments, the movements of the hydro-dissector250 can be controlled circumferentially and longitudinally to controlthe size and shape of the dissection pocket.

In any of the embodiments described herein, high-pressure gas may beused as the mechanism for the tissue layer separation. For example, inany of the embodiments described herein that utilize a form ofhydrodissection for tissue layer separation, the hydrodissecting fluid10 can be replaced by a pressurized gas. In these cases, the tissuelayer separation mechanism 250 includes a source of gas, and a tissuelayer separation actuator, which may be a manually (or machine) operatedpiston mechanism.

In any of the embodiments described herein, the tissue layer separationactuator may include a spring and piston mechanism as opposed to amanually driven piston mechanism. In other embodiments, the tissue layerseparation actuator may include an electrically driven pump, such as aperistaltic pump.

In other embodiments, instead of using fluid to separate the layers 60,61 at the vessel wall, a mechanical device may be used to physicallyseparate the tissue layers. These embodiments create a controlleddissection in the inter-layer space by mechanically separating thetissue layers 60, 61 by advancing a probe forward within the spacebetween the layers 60, 61. In these embodiments, the tissue layerseparation mechanism is comprised of a dissection probe and anadvancement mechanism.

FIG. 30 depicts an embodiment in which the tissue layer separationmechanism includes a dissection probe 280 that takes the form of ablunt, solid, stiff probe. The probe 280 is configured to peal aparttissue layers upon advancement. This embodiment utilizes previouslyachieved access (e.g., through a previously created opening at thevessel wall surface) to insure the correct depth is chosen. Such accessis created by the sub-intimal access mechanism 18. In the embodimentdepicted, the dissection probe 280 is fed into the inter layer planethrough the lumen 24 of the sub-intimal access mechanism 18. This may beachieved through an actuation of an advancement mechanism at theproximal end.

FIG. 31 depicts an alternate embodiment in which the tissue layerseparation mechanism includes a dissection probe 280 that takes the formof a blunt, solid, stiff probe, which acts to peal apart tissue layersupon advancement. The dissection probe 280 is advanced directly throughthe lumen 6 of the conduit mechanism 2 until it exits the sidewaysfacing exit port 7 and enters a previously achieved access openingthrough the inner tissue layer 60. The probe 280 includes a deliveryshaft 282 having a curved shape such that a specific path of advancementis taken upon exiting the conduit mechanism 2. In this embodiment, thesub-intimal access mechanism 18 is removed from the conduit mechanism 2prior to actuation of the tissue separation mechanism 280. As depicted,this embodiment must utilize previously achieved access (e.g., opening)through the inner tissue layer 60 to insure the correct depth is chosen.Such access may be created by the sub-intimal access mechanism 18 inaccordance with some embodiments.

FIG. 32 depicts the blunt dissection probe 280 in accordance with someembodiments. The probe 280 is curved along the width dimension 290 toclosely match the curvature of the taut vein wall. In this embodiment,the probe width 290 is between 0.1 mm and 10 mm. In more preferableembodiments, the probe width 290 is between 1 mm and 6 mm. In still morepreferable embodiments, the probe width 290 is between 2 mm and 3 mm. Innon-venous applications, or in large veins, the probe width 290 may bebigger than 10 mm. In the embodiment depicted, the distal most nose 292of the probe is rounded in the width dimension, while a linear taper 294extends from the rounded nose to the full width of the probe 280. Inother embodiments the linear taper 294 is replaced by a curved chamfer.In the embodiment depicted, the probe thickness 296 is significantlysmaller than the probe width 290. Additionally, there exists a gradualtaper in the thickness dimension from the distal tip 292 of the probe280 terminating at some distance from the distal tip 292 of the probe280 with the full thickness of the probe. In the embodiment depicted,the probe's length dimension 298 is significantly longer than the width290 and thickness dimensions 296. The probe 280 will have sufficientlength 298 to create a narrow pocket sufficient for the necessary pocketdepth of the valve to be created. In this embodiment, the probe length298 is greater than the diameter of the bodily lumen, and is between 3mm and 20 mm. In more preferable embodiments, the probe length 298extends between 8 mm and 14 mm. In still more preferable embodiments,the probe length 298 extends between 10 mm and 12 mm. In anotherdissection probe embodiment, the probe has a radially symmetric shape,with the tip having a smaller diameter cross-section than the shaft,much like a cone.

In any of the embodiments described herein, the dissection probe 280 mayhave a sharp distal tip. In such cases, the probe 280 itself may be usedto penetrate into the wall of the vessel. Thus, the use of the probe 280does do not require previously achieved access through the inner tissuelayer 60 to insure the correct depth is chosen, and thus constitute boththe sub-intimal access mechanism and the tissue layer separationmechanism. In such embodiments, the dissection probe 280 may be fed intothrough the lumen 6 of the conduit mechanism 2, and out of the sidewaysfacing exit port 7. The probe 280 may then be pushed toward the innertissue layer 60. The dissection probe 280 then penetrates into the innertissue layer 60, and is advanced into the inter layer plane between thelayers 60, 61 at the vessel wall. This may be achieved through anactuation of an advancement mechanism at a proximal end.

FIGS. 33a-33c depict different embodiments of a sharp dissection probe280, with different geometries. The probe 280 may be advanced for use asa tissue layer separation mechanism.

FIG. 33a depicts an embodiment of the dissection probe 280 which takesthe form of a hollow needle with a pencil point tip, which is configuredto penetrate into the inner tissue layer 60, then is advanced forward tocreate a narrow dissection plane between the tissue layers 60, 61. Theprobe 280 has a radially symmetric taper from the full probe diameterdown to the sharp tip, which keeps the sharp tip shielded from the innerlayer 60 and outer layer 61 during advancement.

FIG. 33b depicts an embodiment of the dissection probe 280 which takesthe form of a hollow needle with a beveled tip, which is configured topuncture the inner tissue layer 60. The probe 280 may be advancedforward to create a narrow dissection plane between the tissue layers60, 61.

FIG. 33c depicts an embodiment of the dissection probe 280 which takesthe form of a guidewire. The guidewire may puncture the inner tissuelayer 60, and may be advanced forward to create a narrow dissectionplane between the tissue layers 60, 61.

As illustrated in the previous embodiments described with reference toFIG. 31, the dissection probe 280 protrudes from the sideways facingexit port 7, but always remains within the longitudinal confines of theexit port 7. In the embodiment depicted, the probe 280 performs thedissection outside of the conduit mechanism 2, but along the length ofthe sideways facing exit port 7. In other embodiments, the probe 280 maybe configured to perform dissection at other locations relative to theport 7. FIG. 34 depicts another embodiment, in which the dissectionprobe 280 extends out of sideways facing exit port 7, and past the sideport 7. In the embodiment depicted, the probe 280 may perform thedissection outside of the conduit mechanism 2, but along the length ofthe sideways facing exit port 7, or along a side of the conduitmechanism 2, but distal to the sideways facing exit port 7, or distal tothe conduit mechanism 2. The probe 280 may have a sharp or blunt tip.

FIG. 35 depicts another embodiment, in which the dissection probe 280 isdelivered out of an opening 300 at the distal tip of the conduitmechanism 2. The opening 300 is connected to the main lumen 6 of theconduit mechanism 2. In this embodiment, the probe 280 dissects throughthe tissue only beyond the distal tip of the conduit mechanism 2. Theprobe 280 may have a sharp or blunt tip.

In any of the embodiments described herein, the dissecting probe 280 maybe constructed out of a shape memory alloy such as nitinol so that itmay take a specified shape when exposed out of an exit port of theconduit mechanism 2.

FIGS. 36a-36d depict other embodiments of the dissection probe 280,particularly showing the probe 280 having different profiles along thelength dimension 298 so that the probe 280 takes a specific path withthe tissue as it exits the sideways facing exit port 7. In oneembodiment depicted in FIG. 36a , the probe 280 is angled linearly, witha shallow/gentle angle, outward toward the inner layer 60 at the vesselwall. In another embodiment depicted in FIG. 36b , the dissection probe280 is angled linearly outward toward the vessel wall along most of itslength, but takes a curve close to the distal end of the probe 280, sothat the distal section of the probe 280 is parallel or close toparallel to the direction of advancement (e.g., parallel with the tautlumen wall in the longitudinal direction). In another embodimentdepicted in FIG. 36c , the dissection probe 280 takes a tight curveoutward toward the vessel wall, but straightens out close to the distalend of the probe 280, and then curves back at the very distal mostsection of the probe 280. In such configuration, an intermediate portionof the probe 280 is parallel or close to parallel to the direction ofadvancement (e.g., parallel with the taut lumen wall in the longitudinaldirection). In another embodiment depicted in FIG. 36d , the dissectionprobe 280 takes a double curvature, with a tight proximal curve 310outward toward the vessel wall, and a second distal curve 312 slightlynear the distal end of the probe 280. This configuration allows theprobe tip 280 to first contact the tissue at an angle approximatelyparallel (e.g., within 10°) to the vessel wall. Then as the probe 280 isadvanced and the full curvature 312 of the probe 280 exits the catheter,the tip begins to change angle toward the center of the vessel lumen.This embodiment allows for the probe 280 to gain access to the interlayer plane between layers 60, 61, but then helps to prevent fullperforation of the vessel wall by not presenting the outer tissue layer61 with an outward edge of the probe 280 during advancement.Additionally, this configuration helps to pull the inner tissue layer 60inward and away from the outer tissue layer 61, assisting in thedissection.

FIG. 37 depicts another embodiment in which an inflatable balloon 330 isused to push the dissector probe 280 laterally out of the sidewaysfacing exit port 7 toward the vessel wall. The balloon 330 assists inguiding the probe 280 to penetrate into the vessel wall at a certaindesired angle relative to the vessel wall. In other embodiments, anexpandable Nitinol cage may be used to push the dissector probe 280laterally toward the vessel wall.

FIG. 38 depicts another embodiment in which the dissector probe 280contains a suction lumen 338, which communicates with a suction source342 at the proximal end of the conduit mechanism 2. The probe 280contains suction ports 340 on the inward-facing side 344 of thedissection probe 280, which communicate with the suction lumen 338. Asthe dissector probe 280 is advanced, the top most lip of the innertissue layer 60 that has been recently separated from the outer tissuelayer 61 will become temporarily adhered to the inward facing side 344of the dissector probe 280 as it contacts the exposed suction port 340.As the dissection probe 280 is further advanced, the top lip of theinner tissue layer flap slides to other suction port 340 situatedfurther down the length of the dissection probe 280. In otherembodiments, multiple suction ports 340 are replaced by one continuoussuction window. In further embodiments, the probe 280 may containsuction ports on the outward-facing side 350 of the dissection probe280, which communicate with the suction lumen 338. When the probe 280 isadvanced out of the sideways facing exit port 7 at the conduit mechanism2, the suction forces at the side 350 of the dissector probe 280 forcesthe probe 280 towards the vessel wall so that dissection can occur in acontrolled manner.

FIG. 39 depicts another embodiment in which the main lumen 6 of theconduit mechanism 2 is attached to a suction source 400. In this way,suction is imparted on the vessel wall through the sideways facing exitport 7. In this embodiment, an access opening 402 at the inner surfaceof the vessel wall was previously created by another device, and thesuction is imparted on the top most lip 404 of the newly separated innertissue layer 60. As depicted, a dissector probe 280 is then advanced outof the same sideways facing exit port 7 and into the inter layer planethrough the access opening 402. The dissector probe 280 is then advancedfurther to perform a blunt dissection within the inter layer plane withthe assistance of suction on the developing inner tissue layer flap,which helps by stabilizing the vessel wall relative to the device. Inother embodiments, suction is used in the same manner, but the dissectorprobe 280 is advanced through the narrow lumen 24 of the sub-intimalaccess mechanism's 18 tissue engagement mechanism 23. In furtherembodiments, suction is used in the same manner, but no previouslycreated access opening 402 is needed. In such cases, the probe may havea sharp distal tip for creating the access opening 402.

FIG. 40 depicts an embodiment in which a securement mechanism 410 isutilized in place of suction to maintain tension on the inner tissuelayer flap 418 during blunt dissection by controlling the top most lipof the flap 418. In the embodiment depicted, a stitch 412 is placedthrough the top of the lip 418 just as it is first separated from therest of the vessel wall. This suture 412 can be tensioned throughout therest of the dissection or as needed to provide counter-tension duringthe dissection. In this embodiment, the stitch 412 may later be utilizedas the securement mechanism 48, which attaches the flap 418 to anotherbodily structure (e.g., another wall portion) in the vessel lumen.

FIG. 41 depicts another embodiment in which a lip grabbing mechanism 420is introduced to the vessel lumen. The mechanism 420 includes twocylindrical rollers 422, 424 separated by a small gap large enough toaccommodate the thickness of the inner tissue layer flap 418. Asdepicted, the rollers 422, 424 are configured to both roll in oppositedirections, toward each other, so that as they contact the vessel wall,they act to pull the inner tissue layer flap 418 between them. Thebackwards rotation of the distal roller 424 may be facilitated by aservomotor or other form of rotary motor. This can be utilized toprovide the necessary tension for dissection. Some surface roughness isgiven to the rollers 422, 424 to aid in grabbing the tissue. Asdepicted, a jaw like mechanism 430 is utilized to grab the flap 418 onceit is fed between the rollers 422, 424. In other embodiments, therollers 422, 424 roll passively along the vessel wall in the samedirection, until the flap 418 is fed between them.

FIG. 42 depicts an embodiment in which the main lumen 6 of the conduitmechanism 2 is attached to a suction source 400. High powered suctionimparted on the vessel wall through the sideways facing exit port 7 actsto pull the vessel wall a certain distance into the port 7. As depicted,a platform 440 exists within the conduit mechanism 2 to restrict thedepth to which the vessel wall enters into the recess. Suction ismaintained through ventilation holes 442 in the platform 440. In otherembodiments, suction is maintained through a lack of sidewalls in therecess. Once the lumen wall is fully engaged with the platform 440, asharp dissection probe 444 is forced downward, parallel or nearlyparallel to the lumen wall, penetrating only to a specific depth withinthe wall based on the location of the moving probe 444 relative to theplatform 440. In other embodiments, a blunt dissector probe may be usedto separate the tissue layers 60, 61, after a sub-intimal accessmechanism 18 has been utilized to provide an access opening at the innerwall of the vessel. In the embodiment depicted, the sideways facing exitport 7 has the shape of a long oval. In other embodiments, the port 7may have the shape of a long rectangle. In other embodiments, sidewaysfacing exit port 7 may have other geometries, such as a triangular orsemi-circular shape, which will help to shape the inner tissue layerflap being created to a specific geometry.

FIG. 43 depicts another embodiment in which the distal end of thedissection probe 280 carries a very small inflatable balloon 460. Theballoon 460 is inflated intermittently between probe advancements topeal the inner tissue layer 60 away from the outer tissue layer 61. Inother embodiments, the balloon 460 is inflated during advancement of theprobe 280.

FIG. 44 depicts another embodiment in which the distal end of thedissection probe 280 includes an actuating portion 470, which isrotatably coupled to the distal end of the probe 280 by a hinge 472.During use, the portion 470 may be rotated inward toward the center ofthe vessel lumen to separate the tissue layers 60, 61. In otherembodiments, the distal end of the probe 280 may have jaws that open andclose upon actuation, wherein the opening of the jaws is performed toseparate the tissue layers 60, 61. The actuation of the inflatableballoon 460, actuating portion 470, or jaw may be performed manually bythe user, or may be performed automatically based on advancement of theprobe 280.

FIG. 45 depicts another embodiment in which the dissection probe 280 hasthe guide member 100 next to it, wherein the guide member 100 has aleading surface 480, which glides along the lumen wall ahead of theprobe 280, to protect the tissue from taking a sharp angle with thedissection probe 280. In the embodiment depicted, the dissection probe280 is curved and angled to protrude more than the leading surface 480,such that it may engage the inner tissue layer 60. The guide member 100is made of a separate component than the dissection probe 280. In thedepicted embodiment, the dissection probe 280 may exit through a port482 in the guide member 100. In this depiction, the dissection probe 280can be removed from the guide member 100 if needed (e.g., so thatanother device, such as a dilation balloon may be delivered through theport 482 for separating tissue). In other embodiments, the dissectionprobe 280 may contain the guide member 100 in a parascoping manner, bothof which can be inserted or removed as desired. In further embodiments,the dissection probe 280 is a deformed portion of a cylindrical or nearcylindrical tube, such that the portion of the tube or partial tube thatis distal to the probe 280 forms the guide member 100.

In any of the embodiments that involve the dissection probe 280described herein, the dissection probe 280 may be configured to advancewith accelerated or high velocity motion to reduce the visco-elasticresponse of the tissue. The advancement of the tissue layer separationmechanism 280 may be accomplished with a spring force. In other similarembodiments, the advancement mechanism for advancing the tissue layerseparation mechanism 280 may include a piston driven by a compressed gasor electrical motor, by a manual force, or other mechanism for creatingthe accelerated motion. FIG. 46 depicts an embodiment in which thedissection probe 280 is configured to oscillate (e.g., using anoscillator) laterally during advancement, either along a straight pathor along a curved path that closely resembles the curvature of the innervessel wall. In further embodiments, the dissection probe 280 isconfigured to intermittently bend or move slightly inward toward thecenter of the vessel lumen, either while advancing of the probe 280 orbetween intermittent advancement periods. This motion will act to pullthe inner tissue layer 60 away from the outer tissue layer 61 in anon-traumatic manner. In other embodiments, the dissection probe 280 maybe configured to rotate as it is advanced. In some such embodiments, theprobe 280 may have a larger width than its thickness, so that uponrotation, the probe acts to peal the inner tissue layer 60 away from theouter tissue layer 61. In other embodiments, the dissection probe 280may have a radially symmetric shape, and acts to burrow through theinter layer plane between the layers 60, 61 with rotational advancement.In further embodiments, the probe 280 may be configured to have acombination of some or all of these described motions. In any of theembodiments described herein that involves motion of the probe 280, theamplitude of the motions should be small and of relatively highfrequency (especially for lateral vibrations). Lateral vibrations shouldpreferably have an amplitude between 0.1 mm and 3 mm. Motions in whichan object is pealing the inner tissue layer 60 perpendicularly away fromthe outer tissue layer 61 should have amplitudes between 0.5 mm and 5mm.

FIG. 47 depicts another embodiment, in which a specific advancementmotion is created automatically during advancement by the interferenceof strategically placed protrusions 500 on the dissection probe 280 andwithin the main lumen 6 of the conduit mechanism 2. As these protrusions500, 502 pass over each other, they force the dissection probe 280 alonga specific vibratory path. The vibratory path includes a component thatis in the lateral direction perpendicular to the wall of the vessel.This facilitates in separating the tissue layers 60, 61 from each other.

The sub-intimal pocket creation mechanism 32 is not limited to theembodiments described previously, and may have different configurationsin other embodiments. FIG. 48 depicts one such embodiment, in which thepocket creation balloon 38 of the sub-intimal pocket creation mechanism32 is replaced by an expanding shape memory cage (e.g., Nitinol) 510which is held closed prior to actuation by a constraining sheath 512.The sub-intimal pocket creation mechanism 32 is advanced through themain lumen 22 of the sub-intimal access mechanism 18, into the narrowlumen 24 of the tissue engagement mechanism 23, and out of the forwardfacing exit port 25. It is then advanced into the inter-layer plane(created by the mechanism 23) located between the inner layer 60 and theouter layer 61 of the lumen wall. It is advanced far enough such thatthe entire cage 510 is within the inter-layer plane. The constrainingsheath 512 is then removed so that the expanding shape memory cage 510expands to a specific geometry to create the appropriate sub-intimalpocket at the vessel wall.

FIGS. 49a-49f depict different geometries for the expanding component(balloon or shape memory cage) of the sub-intimal pocket creationmechanism 32 in different embodiments. FIG. 49a depicts a geometry inwhich the expanding component 38/510 expands sideways from one side ofthe outer surface of the sub-intimal pocket creation mechanism 32, andis uniformly cylindrical. FIG. 49b depicts another embodiment in whichthe expanding component 38/510 expands symmetrically about alongitudinal axis of the sub-intimal pocket creation mechanism 32, andis uniformly cylindrical. FIG. 49c depicts a geometry in which theexpanding component 38/510 expands sideways from one side of thesub-intimal pocket creation mechanism 32, and has a near triangularcross section, with the largest diameter being very proximal to thedistal end of the mechanism 32. FIG. 49d depicts another embodiment inwhich the expanding component 38/510 expands symmetrically about thelongitudinal axis of the sub-intimal pocket creation mechanism 32, andis of near triangular cross-section, with the largest diameter beingproximal to the distal end of the mechanism 32. FIG. 49e depicts ageometry in which the expanding component 38/510 expands sideways fromone side of the sub-intimal pocket creation mechanism 32, and has a neartriangular cross section, with the largest diameter being very neardistal end of the mechanism 32. FIG. 49f depicts a geometry in which theexpanding component 38/510 expands symmetrically about the longitudinalaxis of the sub-intimal pocket creation mechanism 32, and has a neartriangular cross section, with the largest diameter being very neardistal end of the mechanism 32.

FIG. 50 depicts another embodiment that utilizes a piston like member520 which is inserted into the inter-layer dissection plane through thedissection probe 280, and is actuated to move laterally. It is thenactuated to move toward the opposite side of the vessel lumen to pealapart the tissue layers 60, 61, to create the full dissection pocket 64.In other embodiments, a lever arm may be used as the sub-intimal pocketcreation mechanism 32. The lever arm is inserted into the inter-layerdissection plane created by the tissue layer separation mechanism 28. Ithas the ability to move laterally within the plane when actuated fromthe proximal end. It can also be actuated to move toward the oppositeside of the vessel lumen to peal apart the tissue layers 60, 61, tocreate the full dissection pocket 64.

In another embodiment, a temperature dependant expandable cage is usedto separate the layers 60, 61. In such an embodiment, the device isinserted into the inter-layer dissection plane at a temperaturedistinguishably warmer or cooler than body temperature. Upon insertion,the cooling or heating of this element by the body, acts to transformthe shape of the object into an expanded form, acting to complete thedissection pocket 64. In yet another embodiment, further bluntdissection is done in and around the previously created inter-layerplane to create the full dissection. In yet another embodiment, hingedjaws are used within the pocket to open up to create the fulldissection. In some such embodiments of methods and devices forsupplementing a previously narrow dissection pocket with continueddissection, the device described to carry out this function (i.e.balloon, NiTi cage, piston, actuating tip, jaws, fluid, etc) may behoused within, passed through, or passed over the sub-intimal accessmechanism 18. In other embodiments, this device may be housed in aseparate device, and is fed directly through the main lumen 6 of theconduit mechanism 2. In other embodiments, this device may be feddirectly into the inter-layer plane without using the conduit mechanism2.

The intimal separation mechanism 46 is not limited to the configurationsdescribed previously. FIG. 51 depicts another embodiment of the intimalseparation mechanism 46, in which the backwards-facing cutting mechanism47 is comprised of a backward facing serrated blade instead of a wire,which protrudes from the shaft of the pocket creation mechanism 33. Thisembodiment would be used in the same way as the embodiment describedpreviously, in that it will be deployed with the expansion of the pocketcreation balloon 38, and used to separate the inner tissue layer 60 uponretraction of the expanded balloon 38 through the narrow inlet (e.g.,the one created by the sharp tip 27 of the tissue engagement mechanism23) at inner surface of the vessel wall when the pocket creationmechanism 33 is removed. As similarly discussed, the cutting mechanism47 cuts away from the narrow inlet as the balloon 38 is removed from thecreated pocket, thereby increasing the size of the inlet to provide aflap end with a desired width. In other embodiments, the cuttingmechanism 47 may include a tapered blade. In further embodiments, thecutting mechanism 47 may include two overlapping, scissor like blades.

FIG. 52 depicts another embodiment in which the backwards facing cuttingmechanism 47 is attached to the expanding pocket creation balloon 38itself as opposed to the shaft of the pocket creation mechanism 33. Inother embodiments in which the expanding NiTi or shape memory cage isutilized as the tissue layer separation mechanism 28, and thebackwards-facing cutting mechanism 47 is attached to the back-side(proximal end) of the cage to accomplish the intimal separation. Infurther embodiments, the expanding cage itself has a sharp backside,which acts to cut the inner tissue layer 60 along an intended geometricpath.

FIG. 53 illustrates another embodiment in which the intimal separationmechanism 46 is embodied within the sub-intimal access mechanism 18. Inthis embodiment, the tissue engagement mechanism 23 of the mechanism 18has sharp surfaces 550 on both sides, so that movement (e.g., rotation)of the sub-intimal access mechanism 18 will cause the sharp surfaces 550to cut the inner layer tissue 60 with which the tissue engagementmechanism 23 is already in contact. As shown in the figure, the innersurface of the vessel wall has an opening 552 that was created by thesharp distal tip 27 of the mechanism 23 (or by another device). Movementof the mechanism 23 will cause the sharp edges 550 to cut away from theopening 552 to thereby increase the size of the opening 552. In someembodiments, the user may rotate the sub-intimal access mechanism 18 ormove it laterally side to side while the pocket-creation balloon 38 isinflated within the sub-intimal pocket 64.

FIGS. 54a-54c depict how different embodiments of the intimal separationmechanism 46 can produce a different path of intimal separation, whichdictates the geometry of the newly created intimal leaflet. FIG. 54adepicts an embodiment of a backwards-facing cutting mechanism 47 thatcreates a horizontal line of intimal separation (perpendicular to thelumen wall). FIG. 54b illustrates a backwards-facing cutting mechanism47 that creates a line of intimal separation that is angled such thatthe center of the separation is at the highest point on the vessel wall,and the two endpoints of the separation (cut) occur lower than thecenter of separation, and are near the same height as each other. FIG.54c depicts an embodiment of a backwards-facing cutting mechanism 47that creates a line of intimal separation that is angled such that thecenter of the separation is at the lowest point on the vessel wall, andthe two endpoints of the separation occur higher than the lowest point,and are near the same height as each other. All of these alternatedevice embodiments are used in a similar way as that describedpreviously with reference to the intmal separation mechanism 46 of FIGS.5a and 5b , which involves removal of the actuated intimal separationmechanism 46 from the newly created sub-intimal pocket. In someembodiments, the circumferential length of such a separation line isbetween 90° and 330°. In more preferable embodiments, thecircumferential length of such a separation line is between 160° and240°. In still more preferable embodiments, the circumferential lengthof such a separation line is between 190° and 220°. In the case ofbicuspid valves or other multi-cuspid valve geometries, thecircumferential length may be reduced accordingly by near proportionalvalues (i.e. bicuspid length is about half the monocuspid length).

In any of the embodiments described herein, a cutting mechanism (e.g., ablade) may be used to cut the inner tissue layer 60 prior to dissectionof the inner tissue layer 60 from the outer tissue layer 61. In somesuch embodiments, the blade action is utilized prior to dissection ofthe intima from other layers of the lumen to make a full intimalseparation to the desired width of the valve. In some such embodiments,the blade action is utilized prior to dissection of the intima fromother layers of the lumen to create a narrow incision, and then usedagain following dissection to increase the size of the incision tocreate the full width for the flap.

In any of the embodiments described herein, after the pocket creationmechanism 32 has been used to create the pocket, the pocket creationmechanism 32 (inflated balloon or expanded cage) may be forcefullyremoved through the narrow inlet 65 of the newly created intimal pocket64, thereby tearing tissue to increase the size of the inlet 65. Theincreased size of the inlet 65 provides the flap with a desired width.In such cases, the cutting mechanism 47 may not be needed.

FIGS. 55a-55c depict another valve creation system in accordance withother embodiments. FIG. 55a depicts the system in its first stage ofactuation. As shown in the figure, the conduit mechanism 2, has withinit a connection portal 600 between the two main lumens. Thewall-tensioning mechanism 15 includes a balloon 16 supported on anindependent guide 190. In the illustrated embodiments, the tissueengagement mechanism 23 includes a needle 101 that protrudes a smallamount from the surface of a larger guide probe 100, which acts as aleading edge (as previously described). In the illustrated embodiments,the balloon guide 190 has a track 602 on the side of its surface, sizedappropriately to be able to connect to, and slide over the shaft of thetissue engagement needle 101. FIG. 55a depicts the wall-tensioningballoon 16 when it is inflated out of a side port 7 b at the conduitmechanism 2 during tissue engagement by the needle 101, and duringtissue layer separation. FIG. 55b depicts the balloon 16 afterdeflation. The balloon guide 190 is then retracted a small amount, andthen re-advanced. FIG. 55c depicts the balloon 16 and balloon guide 190after it has been advanced through the connection portal 600 withassistance from a directioning mechanism 604, which is present to forcethe balloon 16 to cross over to the tool lumen 606. Upon crossing intothe tool lumen, the off-center balloon guide track 602 engages the shaftof the tissue engagement mechanism 101 and is advanced along the shaftuntil it extends past the distal end of the tissue engagement mechanism23 and into the inter-layer space 31 that has been created between thevessel layers 60, 61 (as shown). The wall-tensioning balloon 16 is theninflated to create a pocket in the vessel wall. Thus, the samewall-tensioning balloon 16 may function as the pocket creation balloon38, and has the appropriate geometry to create a sub-intimal pocket 64(not depicted). In some embodiments, the independent balloon guide 190may optionally have on it a backwards facing cutting mechanism 47 (notdepicted) as well as a securement mechanism 48 (like that shown in FIG.6) built in, to complete the intimal separation and the valve securement(for securing the valve against a vessel wall, or for securing twovalves together).

FIGS. 56a-56f depict another valve creation system in accordance withother embodiments. In the illustrated embodiments, the conduit mechanism2 only has one lumen 700 and has two sideways facing exit ports 7 a and7 b on opposite sides of the conduit mechanism 2. The wall-tensioningmechanism 15 includes a balloon 16 on an independent guide 190 (aspreviously described). This independent guide 190 has within it aninflation lumen for the balloon 16, and a tool lumen 702 through themiddle. The tissue engagement mechanism 23 includes a needle 101 with abeveled tip 27 that is sized appropriately to fit through the lumen 702of the independent balloon guide 190. FIG. 56a depicts thewall-tensioning balloon 16 after it has been inflated through onesideways facing exit port 7 a, while the tissue engagement mechanism 101is advanced through the lumen 702 of the independent balloon guide 190and extends a small controlled amount out of the other sideways facingexit port 7 b. The tissue engagement mechanism 23 can thus be engagedinto the inner tissue layer 60 with the surface of the conduit mechanism2 acting as the guide member 100. FIG. 56b depicts the needle 101 of thetissue engagement mechanism 23 delivering fluid 10 to dissect tissue inthe vessel wall (i.e. hydrodissection), creating an inter layer plane31. FIG. 56c depicts the wall-tensioning balloon 16 after it isdeflated. FIG. 56d depicts the wall-tensioning balloon 16 when it isadvanced along the tissue engagement mechanism needle shaft 101,advanced out of the sideways facing exit port 7 b, and into the interlayer plane 31. FIG. 56e depicts the system after the conduit mechanism2 has been removed, leaving the wall-tensioning balloon 16 in theinter-layer plane 31. FIG. 56f depicts the wall-tensioning balloon 16after it is inflated again to create the pocket. In some embodiments,the independent balloon guide 190 may optionally have on it a backwardsfacing cutting mechanism 47 (not depicted) as well as a securementmechanism 48 (like that shown in FIG. 6) built in, to complete theintimal separation and the valve securement (for securing the valveagainst a vessel wall, or for securing two valves together).

It should be noted that any of the features described with reference toa figure or embodiment(s) may be combined with any other embodimentsdescribed herein. Also, in any of the embodiments described herein, oneor more of the aspects may be omitted. For example, in otherembodiments, the valve securement mechanism 48 is not needed, and thevalve creation method does not include the act of securing the flap to avessel wall portion. In addition, in any of the embodiments describeherein the valve creation system may include all or some of thefollowing components: Conduit mechanism 2, Angling Mechanism 11,Wall-tensioning mechanism 15, Sub-intimal access mechanism 18, Tissuelayer separation mechanism 28, Sub-intimal pocket creation mechanism 32,Intimal separation mechanism 46, and Valve securement mechanism 48.

It should also be noted that components described as parts of adevice/mechanism may be considered as separate devices themselves. Inaddition, in embodiments in which separate devices are described, theseparate devices may be considered as components of a system/mechanism.

Also, in other embodiments, the embodiments of the devices and methodsdescribed herein may be used twice—once to create a first flap on oneside of the vessel, and again to create a second flap on the oppositeside of the vessel. In some embodiments, the two flaps may optionally besecured by the securement mechanism 48, as similarly described herein.

Furthermore, although the various embodiments of devices and methodshave been described with reference to blood vessels, in otherembodiments, the devices and methods described herein may be used tocreate tissue flap in any bodily lumen in which valve creation isdesired. Also, embodiments of the devices and methods described hereinare not limited to being used to treat venous reflux. In otherembodiments, embodiments of the devices and methods described herein maybe used to treat reflux (or other medical conditions) in other luminalstructures inside a patient.

Although particular embodiments have been shown and described, it willbe understood that they are not intended to limit the claimedinventions, and it will be obvious to those skilled in the art thatvarious changes and modifications may be made without departing from thespirit and scope of the claimed inventions. The claimed inventions areintended to cover alternatives, modifications, and equivalents.

What is claimed:
 1. A method for gaining controlled access to aninterior portion of a wall of a blood vessel, the method comprising:providing an elongated member having a longitudinal axis, a proximalportion and a distal portion having (a) a wall tensioning mechanism, and(b) a slanted surface spanning a length of the distal portion in alongitudinal direction and extending across a cross-section of theelongated member, wherein the slanted surface forms an acute angle withrespect to the longitudinal axis; positioning the distal portion of theelongated member at a treatment site within a lumen of the blood vesselsuch that the elongated member extends along a longitudinal axis of theblood vessel; while at least the length of the distal portion remainsextending along the longitudinal axis of the blood vessel, positioningthe slanted surface in apposition with a first portion of the bloodvessel wall at the treatment site, thereby conforming the portion to theslanted surface to position the portion at the acute angle; extending atissue penetrating element from a port on the slanted surface topenetrate an interior surface of the blood vessel wall along the portionin apposition with the slanted surface; and expanding the walltensioning mechanism at the treatment site such that the wall tensioningmechanism projects radially outwardly away from a side of the distalportion opposite the slanted surface and contacts a second portion ofthe blood vessel wall circumferentially opposite the first portion whilepushing the slanted surface into the first portion of the blood vesselwall such that the first portion of conforms to the slanted surface. 2.The method of claim 1, wherein the wall tensioning mechanism and theslanted surface are located at the same location along the longitudinalaxis of the elongated member.
 3. The method of claim 1, furthercomprising advancing the tissue penetrating element distally within aninterior region of the vessel wall while the wall tensioning mechanismis expanded and the slanted surface is in apposition with the portion ofthe blood vessel wall.
 4. The method of claim 1, wherein the tissuepenetrating element comprises a tube having a lumen, and wherein themethod further comprises delivering fluid through the lumen of thetissue penetrating element to an interior region of the blood vesselwall at the treatment site.
 5. The method of claim 1, further comprisingdelivering fluid via the tissue penetrating element to an interiorregion of the blood vessel wall at the treatment site.
 6. The method ofclaim 1, further comprising delivering fluid via the tissue penetratingelement to an interior region of the blood vessel wall, thereby creatinga pocket inside the blood vessel wall.
 7. The method of claim 1, furthercomprising creating a pocket within the blood vessel wall at thetreatment site.
 8. The method of claim 1, wherein extending the tissuepenetrating element from the port on the slanted surface includespenetrating the blood vessel wall without puncturing through the bloodvessel wall.
 9. The method of claim 1, further comprising creating aleaflet from the blood vessel wall at the treatment site.
 10. The methodof claim 9, wherein the leaflet has a length measured along alongitudinal axis of the vessel.
 11. The method of claim 1, furthercomprising advancing the tissue penetrating element within the bloodvessel wall generally parallel to the longitudinal axis of the bloodvessel.
 12. The method of claim 1, further comprising advancing thetissue penetrating element within the blood vessel wall generallyparallel to the longitudinal axis of the distal portion.
 13. The methodof claim 1, further comprising advancing the tissue penetrating elementgenerally parallel to the longitudinal axis of the blood vessel betweenan inner layer and an outer layer of the blood vessel wall.
 14. Themethod of claim 1, wherein extending the tissue penetrating elementcreates a space within the wall of the blood vessel, and wherein themethod further comprises positioning a component in the space forincreasing a size of the space.
 15. A method for gaining access to aninterior region of a wall of a blood vessel, the method comprising:providing an elongated member having a longitudinal axis, a proximalportion, a distal portion, and a wall tensioning mechanism at the distalportion, wherein the distal portion includes a slanted surface extendingacross a cross-section of the elongated member that forms an acute anglewith respect to the longitudinal axis; positioning the distal portion ofthe elongated member at a treatment site within a lumen of the bloodvessel; expanding the wall tensioning mechanism at the treatment site toposition a portion of the blood vessel wall at the treatment site inapposition with the slanted surface, thereby conforming the portion ofthe blood vessel wall to the slanted surface and positioning the portionat the acute angle with respect to the longitudinal axis of theelongated member; and penetrating an inner surface of the blood vesselwall along the portion in apposition with the slanted surface byextending a tissue penetrating element distally from a port positionedalong the slanted surface, thereby gaining access to an interior regionof the blood vessel wall.
 16. The method of claim 15, wherein theelongated member includes an inflation lumen in fluid communication withthe wall tensioning mechanism.
 17. The method of claim 15, whereinextending the tissue penetrating element creates a space within the wallof the blood vessel, and wherein the method further comprises placing acomponent in the space for increasing a size of the space.
 18. Themethod of claim 17, wherein the component comprises an expandable memberor an articulable member.
 19. The method of claim 15, further comprisingdelivering fluid via the tissue penetrating element to the interiorregion of the blood vessel wall at the treatment site.
 20. The method ofclaim 15, wherein penetrating the blood vessel wall occurs withoutpuncturing through the blood vessel wall.